Missing 2 months of school is no problem, trust me. My friend missed the 2nd quarter almost entirely due to being sick during junior year, which is the worst time to be missing from school. He never stopped trying, though. In the end, he managed to get through with all his classes with an acceptable grade (A, B, since he wants to go to a top 10% uni).
Just keep working at it. No one is going to make you feel worthless because people care about you. Something small like missing deadlines or not doing some stuff isn't going to make people dislike you or anything. It's part of human nature to fail sometimes. In fact, people respect you more if you manage to come back up from a deficit. It shows that you are able to overcome the obstacles that life throws at you.
Your real friends don't judge you from what you do, but what you are. They may seem to be different towards you now because you yourself are different towards yourself. Get back to your old self, and your friends will too. Work hard in school, the next year and a half are going to be rough but it'll be worth it if you manage to get through it.
Depression is a hard thing to get through, but most get out of it eventually. If you need to go to a therapist, you may want to do so. A couple grand might make or break your future.
Just do what you need to do, we're here for you if you need us.