This is a deep question that you likely won't find the answer to on the internet. You should talk to therapist and get this stuff out. Realizing it is the first step though.
if I’m not being useful to someone or supporting someone else or doing something worthwhile then I’m a waste of resources
Get that shit out of your head right now. You didn't ask to be here and you don't owe anyone shit. You are going to die someday and nothing will matter other than if you did what made you happy.