First, the issue that came up between you and the father is kind of classic. It's a common communication problem between men and women. The woman states her fears about the relationship, and the guy feels attacked. His response is also very common. He got defensive. This doesn't mean that he actually didn't feel the same about you. He just felt very disappointed. Now his feelings are probably starting to fade as he launches into this whole new thing in life, boot camp, and it can be very overwhelming, too. I know this part can be hard to hear, but it's true. The good news is, feelings can change. You two can work on this. It might be that you will rekindle what you had started.
I'd tell him immediately, and try not to burden him with the relationship part of it. Just tell him what's going on, what you think you might do (keep the baby or give it up for adoption; I hope you won't consider abortion at this late date, but that is for you to decide).
I would tell him that I'm sorry about the way I brought up my fears and didn't mean to make him feel defensive - that I was just stating fears but that I truly did feel that he was different from other guys - and was voicing my fears to get his confirmation that he really was the special person that you had found.
I'd start with this. Be friendly, try not to be dramatic. Then, whichever way he responds, tell him about the pregnancy. Don't wait. It's only fair to tell him, because this is his child, too.
Now, about adoption. It is a very, very painful thing to do. But so is raising a child without the father involved, or in a less than ideal situation. I know a lot of moms out there would like to say otherwise, and will be mad at me for saying so, but, D., this is reality. I have found that it's very hard to care for a baby *with* my husband coming home every night, being a dedicated husband and father, and very involved, changing diapers at least as much as I do. Even so, babies have so many needs. In the first several months, you might not even be able to pee without that baby in your arms, or else you might have to leave that baby in the crib to cry while you do, and you will find that incredibly hard to do. The baby might wake up at 2 in the morning and you have to be up, too, no matter how exhausted you are. You could be up for hours every night, then have to go to work in the morning. It's just incredibly, overwhelmingly constant. Some days, I barely managed to brush my teeth, before my daughter grew up to the point where she could entertain herself a bit every hour (around 9-10 months of age). Some babies are easier, but not many.
I'm saying that, if you want to pursue college, adoption is about your only chance. I got pregnant when I was in high school, and I decided to give my son up for adoption. The night I said goodbye to him was the hardest moment of my life. I won't tell you otherwise. I cried, non-stop, for about four hours. For months afterward, I grieved. But it got better, and I got to send him letters and birthday presents, and his adoptive parents sent me pictures and updates. It was a semi-open adoption. You could opt for an open adoption, if you choose adoption. It's wonderful because you can spend time with your child, maybe a couple of times a year, and really, you'll find that that's all you need, and you'll be happy that s/he is in a good family who loves him or her so, so much.
If you choose to keep the baby, with or without the father being involved with *you*, bear in mind that he is responsible for child support, so you will have that financial help, at least. And you can do so much for your parenting experience, and of course for the well-being of your child, to do as much research as you can to learn how to care for a baby. I cannot stress this enough - and it doesn't matter whether you're 19 or 39, this is true. Instinctive parenting is great, but there is SO MUCH that instinct won't tell you. Read everything you can get your hands on.
I recommend the Sears books, and anything by Becky Bailey or Mary Sheedy Kurcinka for psychology/behavior questions.
Please email me if you have other questions. I will be more than happy to help in any way that I can.
PS even if you aren't decided about what you're going to do yet, I'd contact an adoption agency. They have social workers who can talk to you objectively about what to expect. A good adoption agency will get you in touch with counselors so you can work through what you're feeling and make sure of what you want to do, and help you get through it. The adoption agency will probably also give you workbooks to go through and they're extremely helpful in deciding what you want to do. A good agency wants mothers who are sure of what they want to do - they don't want legal issues later and botched adoptions, so they won't pressure you at ALL. If you do have the baby adopted out, by the way, your medical bills will all be paid in full.
Again, email me if you have any other questions.