He knows how babies are made right? As a PP said, he won't wear a condom, won't get a vasectomy, but it's your fault for getting pg? good lord
I can't tell you what to do. But if it were me, I'd be choosing that baby over him. Do you believe that even if you terminate, that 5 years down the track you are even going to be together anyway? The pg aside, the relationship sounds like it's in a bit of trouble, and I'm going to go out on a limb and say if you terminate, you'll probably end up breaking up down the track anyway, and you will have lost the baby and the marriage.
If YOU don't want to keep the baby, then terminate. But reading your OP I get the vibe you do want to keep it.