I'm burnt out on helping my friends but I feel guilty for not being more supportive.
Why do you think this is making you feel guilty?
I feel overwhelmed by them needing my help all the time.
You should not be expected to take care of other people all the time. It is good to take time to your self.
I'm going to be selfish for once and stop helping people when I don't want to.
Yes, taking care of yourself will ultimately be best for everyone. You can't help them at all if you're totally burned out all the time.