Realtionship has taken a bad turn, please help!

i've been going out with my boyfriend for 6 months now, I met him online on a dating site, he lives in a different city from me with his dad (but not too far away) and his mum lives in the same city as me. everything started out great, we only met up at the weekends we would go into town in the shops, have a coffee ect..
started to get more serious and I started staying at his mums house with him, we would have sex about 2/3 times a day on the 3 days a week that I see him (friday, sturday and sunday),then money got tight and we couldn't afford to go out anymore, so we would stay in and bake instead. about 3 months in he started getting lazy, he would go on his xbox for hours and ignore me and I noticed that he no longer tried touch me to get me in the mood, and alot of the time when i would try he would tell me he's not in the mood but i put that down to him being upset about his nan dying.
it picked back up but now it has gotten even worse than before since he's found his work experience placement about a month ago, he has been getting my hopes up by telling me he is coming to see me then doesn't bother telling me he can't until last minute, and he only tells me if I contact him, I seem to have to arrange everything and do the chasing, the other day I told him it was making me very upset and he said 'well if it makes you that upset, why don't you dump me and go off with one of those other lads you always talk about, my life couldn't get much worse anyway' I don't talk to him about any other lads, he has asked me on a couple of occasions about 2 months ago about a couple of my guy mates that I was talking to over facebook, one of which fancies me, I told him that they were just school mates and told him that i wasn't interested in them. what he said made me incredibly upset and i told him again that I want him, not anyone else, explained to him how much he means to me, he is the only person that I have trusted enough to tell all my secrets and somehow be naked infront of which is very difficult for me. he told me if it was going to work I would have to accept that he might not be able to come down every weekend, fine I said 'fair enough but you have to let me know if you won't be because it's not fair to get my hopes up'
he then said we were having too much sex and he felt like our relationship was based on it. I told him that it is important for me because if makes me feel like we are connected as its something that we do only with each other, he said that we didn't need to do it 5+ times a day to feel connected, but we haven't been having that much, last time we did it about 3 times a day as I hadn't seen him in 2 weeks and I was due on and I get alot hornier around that time, but usually we don't do it that much, why is he saying that we do it too much when majority of men wouldn't pass up sex and/or say they aren't getting enough? I am almost 17 and he is 20, also 2 weeks ago his step dad, who is in his 40's, sexually assulted me, started rubbing my nipples through my nighty and asked me to get my breasts out for him but didn't of course, which he knows about, do you think that could be making it worse? sorry for the long post but please help.

whoa you dropped a big bomb at the end of this post- still trying to get my head around that- what happened after you told him what his stepfather did??!! that's really disturbing and a huge deal, and it's weird to me that you just slipped this info in at the end of your post...i feel like this definitely would have a huge effect on the relationship and his family dynamics as well- has the issue been discussed w/ his mom? the rest of his family?

yeah i didn't really know where to place it so I kind of just put it at then end. at first my boyfriend didn't seem to concerned because he thought that he was just saying rude things to me and said that he was just drunk and didnt mean it but i told him when he was sleepy so he didn't take all of it in, when he asked me a few days later why i was still so upset I re-told him and then he did seem concerned and said he wanted a word with him but in person which he hasn't done as he hasn't been down but the problem about the sex has been going on for a while before that. it hasn't been discussed with his mum yet but my parents are going to contact her about it.

did you mean the sex with your boyfriend has been going on for a while before that? not with the stepdad, right??? i had had the impression he had just touched your breasts inappropriately- i really hope it was not even worse :((
i'm glad to hear that you''ve told your parents and that they are going to talk about it with his parents...i feel like this would definitely have a huge effect on the relationship and you should not go over the house with his stepfather there ever again.
i hope everything goes well with the discussions, make sure not to let it slide and get worked out...

So what's going on in your boyfriend's life - you touched on a work placement and money issues, what kind of stress is he under? He could well be depressed, which could explain why he's trying to push you away.

You never go to that house again. You never see that boy nor his step father again. I can't believe you don't consider that to be the body of the post.

yes i ment with my boyfriend not the step dad, although his step dad has asked me a couple of inappropriate questions before like 'do you watch porn? and what porn do you like?' and 'what turns you on?' which i just 'don't know because i don't watch' and to the other question 'dunno, just the usual stuff I guess' and the changed the subject

thing is when I am stressed I seek comfort in my loved ones, not push them away. he didn't really seem all that stressed about it, and if he was then he would of told me, well at least he usually tells me. what I don't get is, he says he doesn't want the relationship to be based on sex, that he likes just kiss and cuddle times too, but he hasn't bothered to cuddle me very much. I mean if I wanted more cuddles I would just sit with him and cuddle him or ask him if we could have cuddles, so why hasn't he done that? very confusing :(

WHOA. Huge bomb at the end there. You should never go to that house again. Seriously. What if it gets worse? What if he rapes you. THAT should be your main concern. And why the hell is your boyfriend okay with that? What the hell? He should be VERY concerned

Dont go back there!! Your only putting yourself in danger. That step dad did the wrong thing and your bf did the wrong thing by not being more concerned!! For your own sake I would leave that family alone. Maybe even go see the cops about it if your comfortable enough. What if he does it to another girl that comes along... and worse???? What he did was wrong on every level. Please Please Please dont go back their hun for your own sake. You dont deserve that. Dont put up with it!!

I am not going back there ever, certainly not now my boyfriend has dumped me..