I agree with K. on the paternity testing. That's the best proof.
Also, I notice that you did not deny having sex with other people? You only said that you know it's him...
If he's the ONLY person you've had sex with, then there's nothing to worry about. But, if you've had sex with anyone else, even one time, then you really have no way of knowing other than to have each of the men you've had sex with have the test.
Sorry, but K.'s comment on the Maury show got me thinking of how many women have actually been proved wrong on that show...:eek:
Now even if you do prove that your boyfriend is the father, there's no way to make him be a part of your child's life other than financial support. It really sucks, but that's how it is. You cannot control another person or make them do something that you would like - even in this situation.
You really need to ask yourself how you want to proceed knowing that raising and caring for this child will be your sole responsibility. Is that something that you want and are ready for. I'm not telling you what to do, just make sure that you explore all of your options and choose the one that you feel is best for you, and your baby if you decide to deliver.
I'm not trying to be doom and gloom - just asking you to take an honest look at your situation. Listen to the advice of others, but do not let them coerce you into something you don't want to do. No matter how good the intentions of your family and friends, this is your situation to deal with - not theirs.