I think you're looking at this from the wrong angle. Your decision about whether or not to keep the baby SHOULD NOT depend on your boyfriend and what HE feels about all this. It should depend on YOU and how YOU feel about being a mother. Actually, you're kind of lucky because you're getting some information up front that a lot of women aren't privy to. What I mean is that you already know now that he's going to abandon you and take no responsibility for his actions. This is better than learning that sad truth when the baby's a year or two old and you're already locked into a course of action.
Stop focusing on him. From what you've told me, it's over. He will not "see the light" nor will he "cool off and come to his senses" after he's had time to adjust. Hoping for this is little more than wishful thinking and in the end it'll only leave you feeling like a pathetic failure because he'll always tell you it's your fault he left. YOU were nagging him too much, YOU got pregnant without consulting him (my personal favorite, as if you masturbated your way into this condition) and YOU won't give him any space and freedom. I don't know the whole truth about your break up but it seems like he simply doesn't want to commit and be responsible yet. That doesn't make him an evil person (just selfish and immature) but it will make him a terrible husband/father, so just him go.
Once you've done that, your decision will be simpler. It will no longer boil down to someone else's motives which are out of your control. Are YOU ready for the incredible responsibility and hardship of being a single mother? Do you want to have a child and enjoy the miracle of motherhood? The price is high, but the rewards can be well worth it if you're into kids. The bottom line is that the choice is YOURS and that it should be made with YOUR wants and needs in mind.
If you don't want to do it, there are many options. Most adoption agencies will take good care of you while you're pregnant, so you can take those months to get yourself together and figure out what to do with your life. However, don't choose adoption if you have even the slightest suspicion that you'll back out at the last minute. This is a cruel thing to do, because it costs someone else a lot of money and almost always breaks a heart or two.
If you think you'll cave at the last minute, go ahead and have an abortion. Contrary to what you'll be told, it is NOT homicide and you WON'T spend the rest of your life "hearing your dead baby's screams." (Some folks can be quite cruel in their quest to shove their beliefs up other people's butts.) It will be expensive (unless you live in California) and there will be some pain and emotional conflict, but you'll get through it.
Finally, if you decide to be a mother to this baby, be prepared to feel quite alone and terrified. Pro-lifers will swear to you that "you will get all the support you need," but you will not. The child support office is apathetic at best. Unless the father is middle class or better, they won't bother hunting him down. Welfare, food stamps, and subsidized child care will only trap you in a cycle of poverty that will slowly drain your spirit and may even make you resent this child for holding you back.
The only way I would recommend going through with motherhood is if you have a close family and a STRONG support network of friends and loved ones. Otherwise, that child will feel like a lead weight tied around you everywhere you go, no matter how much you love it. The most expensive thing about raising a child is supervision. Who will watch him/her while you work or go to school? In most states, day care runs over half of a full time minimum wage salary and the subsidy programs are usually sadly underfunded. Your social life will be stunted, especially where romance is concerned. A lot of men don't want to deal with single mothers, not because they don't care for the children but because they don't want the drama and stress of having Daddy pop in and out of the picture.
Anyway, I'm babbling because it's late and I feel for you. No matter what you decide, I wish you well and hope that you make the choice with you and your child in mind. Nobody else should matter!
