My boyfriend and I have been together just shy of 4 years. We lived apart for the most of it due to his job, but 4 months ago we bought a house together and now see one another daily.

We use to have fun, great sex, romance, passion etc. Now it's like it's all dead in the water. He says I pressure him into having sex and it feels like a chore. But the less we have it, (down to once a month) the more it gets frustrating and it starts to bother me. On top of that, he looks at a fair amount of porn, telling me that it's all he was use to before he met me.

Anyway, I have tried to talk to him, tried to get some answers, and all he does is get mad, put his head down, won't look at me, tells me it's because I pressure him and he doesn't know what to expect out of me from day to day cause he's walking on egg shells... which is BS. He completely avoids the question, and then in the end, tells me he doesn't know why.

I love him to pieces, but I believe that intimacy is an important part of a relationship, and with out it, it's going to fall apart because of distance, or an affair. And I've already had one man do that to me...

HELP!

Maybe the new living arrangement is stressful to him. Buying a house together is a big step, maybe that is stressful. Maybe it is his job, but if he won't talk about it, it won't help.
He needs to understand that you two need to communicate.
Try talking to him in a non confrontational way.
It also could be the adjustment to living together although I don't know why he does not want to have sex. Do some couples counseling?

I am sure the new living is certainly and adjustment, but shutting me down and out is not going to solve anything. He doesn't like to talk about anything unless he feels there's something to say. He dances around the subject at hand, and it's getting stale. I can't get a straight answer over anything. As for couples counseling... it has come up in conversation some time ago, but shuffled to the bottom of the list. Aside from that, he doesn't see that anything is wrong... he says it's just me.
I'm at a loss. I end up apologizing and accepting the blame because it's easier :(

Well that is not the route to take, There is a problem because you are unhappy. You two need to go to counseling or begin to communicate or you're not going to make it. Sex once a month is in my opinion unacceptable in a young couple.
Stop apologizing for what you don't mean and take a stand.

I understand all that, and have tried to tell him that, but he won't have anything to do with it. All he does is put words and feelings into my mouth that he is worthless and such to the point I give in. He speaks of his stress as he is the only one that feels it, and it makes it very hard to communicate on a calm level. So... we get further apart, less passion, less everything, and he still thinks nothing is wrong. I gave up everything to move here and support him and his job, and things are sinking fast, and it's scary.
It's like I have caught him in so many lies, that he doesn't even know what the truth is cause he can't say it to avoid the hurt feelings. With all the things I have caught him doing, all the forgiveness I have given for them, I feel unworthy and less then valuable. It's heart breaking.
And you are right... I need to take a stand. I am not perfect, nor have I ever implied that to him. He knows every dark secret of mine... the funny thing is, I don't think I know his.

Then you need to decide if you want to continue on with this. If he does not want help, if he does not want to work on things, you can't make him, but you can decide if you want to deal with this.
I wish you well.