Need adivice with complicated situation

Hi, I'm new to the forums, nice to meet you all...

So im looking for some advice, im in a situation were i really don't know what to do...

for 5 months now ive been dating this girl, we met in college. Heres the thing, she has a daughter, this really doesnt bother me at all, actually i get along very well with the kid and i realy enjoy being with both of them... The problem is that the girl's father is still around, i havent really met him personally, and he has seen his daughter maybe 4 times total... Lately this guy has been showing up more, he has been sending sms to my girlfriend and stuff like that, this is really making me feel terrible, everytime he comes to my mind i cant stop myself from thinking that he was with my girlfriend and he touched her and i don't know... it really feels horrible, i don't like feeling this way.

I know i can't do anything about this, i can't make him go away, and thats my biggest fear, i really love my girlfriend but i don't know if i can handle these feelings... is love worth this horrible feelings? Should i keep trying to get over this? Should i let her go?

I know some people might say that i shouldve thought about this before, i really did, but i never expected to feel this way...

well if you can't get over the fact the she has a past, then I think it is unhealthy that you stay in this relationship with her....for her sake and yours..the father will always be there....

can you not try to overcome this, have you not had a past?

I do have a past, just like everyone, my girlfriend knows everything about it, and i thank her for loving me regardless of it... the thing is that my past lives only in my head, theres nothing to remember me or her about it... but with her its something else, this guy is like a ghost of her past that won't let me overcome it...
I've been trying to get over this but i dont know how... everytime the guy contacts her, its like i become someone else, i get upset, don't want to talk, i feel really hurt... Even though i don't want to, im killing our relationship...

you are missing my point....he is the father of her kid, you either deal with it or you dnt....and you know you can't change that, he will always be around, if you can handle that...work on getting over it...if you can't.......

How can i get past that? i don't know how... ive handled this for 5 months but im not sure what happened recently that made me feel like this...

work on it....Bacchos...if you want to keep this relationship going, you're going to have to....

meet the guy? i dnt know, maybe you will realise what a douche he is and that he is no match for you...I dnt know how you're going to do it...but the point is you have to because he is going no where (unless he is a dead-beat daddy).....come on LF and rant if you have to, it really comes down to how much you love this girl.....

We'll he's going to be around until her kid is an adult, so get use to it. Plus if the child is still a baby, chances are they were overwhelmed with parenthood and when life settles down there's a chance they'll get back together.

Keep your eyes open and be prepared.