In this situation, do you think I should take my ex back?

[Dices]

I realize that this is 100% my decision, and I'm the only one who can actually decide. I just want to know peoples' thoughts on it, because I think they might help me with deciding what to do. Thanks very much... (I'm 19, she's 17). I'll make a list of the basics at the end for those who don't really have the time to read the full story. Thanks a lot!

Here's the scenario: I had been with this girl for a year and eight months, and for that year and eight months, it was amazing. We were always completely honest with eachother, we totally trusted eachother, and we had an amazing connection and chemistry. After a year, we talked about our future, and how we wanted to be together always, and it was 100% honest at that time; of that I'm sure. But here's what happened:
My ex was, for her entire life, a total goody-twoshoes. She never broke ANY rules or did ANYthing that would be disapproved of (well, that depends on who you are, I guess... we had no problems having sex after being together for 5 months, and continuing at least once a week till the end). About a month ago (we've been broken up 3.5 weeks), she told me she was going through a rebellious phase because of how strict she'd been with herself for her entire life, and I totally accepted that. She said she wanted a bit of time to herself as well, which would entail breaking up for a little while (this was actually decided upon the day we broke up). I said I understood, which I did, and we broke up on great terms with eachother, with every intention of getting back together in a few weeks. However, the next week, when we decided to talk just to say hi, she said she wanted to lose the notion of us getting back together soon, because it's not really freedom if you're still bound to another person. I understood this as well. The next week, when we talked again, she said she didn't really miss us. This messed with my head a lot, because I had been missing her desperately each minute. I didn't go into detail on that, because I thought that would push her further away. I did let her know that I missed her a lot, though. After a few more days, I decided that I really couldn't wait any longer because I was so scared of losing her. While 2.5 weeks may not seem like a lot to many couples, this girl and I are neighbours, and we had been together or at least talked every single day for the year and 8 months we were together. I asked her to please choose whether or not she wants to get back together and try to make things work, or if she really wanted to end it for good. I said this because I said I couldn't keep going on waiting for her, not knowing if she would ever come back, and it was killing me. She decided, on the third week we had been broken up (last thursday), that she wanted to say goodbye. She said, with complete honesty, that she really didn't miss us that much. I asked if the reason for breaking up had anything to do with another guy. She promised it wasn't (and I believe her). However, on Saturday, I found out she was spending the night at one of her allegedly "friend only" guy friend's house. The next day, on Sunday, I said I just really wanted to understand, and I asked her if she could just come talk to me for 5 minutes to see if I could understand whether or not I really had to move on. The prospect of moving on was so hard because what we had was so powerful. Something to note is that she refused, on the basis that she was "too busy," yet she had time to spend 18 hours at this guy's house and she couldn't spare me 5 minutes after all we had been through together. I had to beg for the 5 minutes, and only got it 4 hours later. In between that time, some of her and my friends told me that she was saying I was being really annoying, and that she was sure we were done for good. Anyway, when I asked her what she felt for this guy (who, for some perspective, is a complete asshole [i'm not just saying that, absolutely everyone thinks so], he's insensitive, he's not the least bit attractive, and he has nothing going for him... my ex is beautiful, smart, and atheletic). She said they were only friends, and I said "you don't just spend the night at a guy friend's house after we just broke up." I asked her repeatedly if anything had happened, and she said no, but I could tell she was lying. I persisted, and she admitted that they kissed. I persisted, saying that "you don't just spend the night at a guy's house, kiss, and leave it at that"... and she continued to deny anything had happened. I persisted a good 4-5 times with this before she admitted to making out with him. I know with 100% certainty that that is the full truth. After I told her how much she had hurt me by lying, and by walking out on me without even missing me, and how she'd thrown away something so special, precious, and rare for a fling with a stupid prick that didn't even care about her (he was just trying to get into her pants, as a good friend of his told me). The promised 5 minutes turned into an hour and a half, as she instantly regretting everything, and bawled for an hour to me about how sorry she was and how much she f***ed up. She said she desperately wanted me back. I told her exactly what I felt and what I had been through in the past few weeks trying to make sense of everything (and as anyone who's gone through a breakup with a serious girlfriend knows, it's hell).
The problem is, setting aside even the fact that she lied to me over and over (keeping in mind that all of that is in the span of 24hours), my confidence in the permanency of our relationship has been severely damaged. I don't want a casual relationship, and neither did she, and now I'm not sure. She says she does, and I know she's being totally honest about that, but I don't know if she'll feel the same way in a month or two. Like, what's to say that this won't just happen again; her walking out on me without a bit of regret, and messing around with a random guy so soon after (I also don't know how much further that would've gone if I hadn't found out and confronted her). But, she has never lied to me before. She never acted anything like she has in recent days before. Even though she tells me, and I believe her when she says it, that she loves me and wants me back, I don't know if she's actually ready for a serious relationship given everything that's happened in the past month.


IN SHORT:
Pros:
-We had an amazing 1.7ish years.
-She was an AWESOME girlfriend.
-She was always 100% honest with me before being dishonest with me about making out with a guy this past weekend (noting that I had to push and push for that honesty.. she said she didn't want to hurt me by saying it).
-She's never done anything like this before ever, which suggests that it may have just been a phase after being so strict with herself for so long
-She is genuinely sorry and regretful for what she did to me and how she damaged us

Cons:
-My trust and confidence in the security of our relationship has been severely damaged.
-I never did anything to deserve this. Totally honest, as she, all friends and family agree, I was an AMAZING boyfriend to her.
-She lied to me over and over about saying she hadn't made out with this other guy, until she finally told me the truth after a lot of pressuring. While this was in the span of 30 minutes, I also think it's dishonest to have no told me about him when we had talked the previous thursday. Although, one must consider that she thought we were done for good, and that she was sparing my feelings by not saying anything.
-I'm no longer sure she's ready for a serious relationship anymore. She definitely was before, but I don't know if she is anymore. I don't know if she'll pull something like this again in another 6 months or something (it'd obviously be done for good, in that case).


Here's what I decided so far: I said I would give it a minimum of a month before making up my mind (I don't want to decide too soon) on whether or not we should be together, and if she can somehow show me that her love isn't something temporary, then we can get back together. I just don't know how I'm going to be able to trust in it again, but maybe I will in time? What do you guys think? Any serous thoughts and comments are greatly appreciated. Thanks SO much for your time, it really does mean a lot to me.

[jayjaym]

if im being totally honest and through experience if its happened this once then im pretty sure its going to happen again, aswell as the trust being broken you are both very young and there will be other spanners thrown-in in the future.

i could be wrong it might be a one off but once she gets back into a routine with you will she think its the grass greener ont he other side again?

i know it sucks, but only you will know what the chances are of this happening again.

[robFord]

I know a year and a bit seems like a long time since you're still really young but in the grand scheme of things, it really isn't. Relationships can recover from something like this but there's always going to be feelings of resentment and mistrust going forward. Do you really want that? You're doing the right thing by waiting a month to decide, don't rush back into anything because it'll just make things worse.

I was in a similar situation as you but I was the one that backed off and fooled around with someone else. I begged and begged to get my gf back, and eventually she did. We ended up staying together for another 3 years (some hiccups along the way of course) but we always knew that we were good together. It took a long time for her to get over the pain I caused her and my indiscretions eventually lead to her cheating on me because "hey, why the hell not? it's not like we're the perfect couple anymore".

Take a step back and figure out what you want and deserve. Does your love for her out weigh the feelings of hurt when she lied to you and hooked up with some other dude? If she's already straying, chances are it'll happen again.