Oh dear I was in the same boat around Christmas! It's better to break it off as soon as possible. Maybe just say you don't want to possibly jeopardize the friendship. Get it done now though because it's not fair to you OR him and you'll both be wasting time
If it's getting annoying or is in any way inappropriate, cut it off now. However, if he is not completely mean, wait. You don't want to be unkind. Funniest thing to do would be to say "You're like a brother to me," But that would be mean and awkward, so it's best to just wait it out...
You should make sure yourself is stable enough to have and care for a child, have enough food for the child, a job/career, etc. There is many different answers to this