Are you sure you're not falling back to S because he is something that you know and that you're comfortable with? Is he someone you really want to stay with? Are you sure he will not go back to his video games? Or, if you let S back into your life you can start off new and not move back in with him for a yearish? to make sure he is committed to a future with you.

Maybe you should focus on your future and not worry about romance too much. You could work towards an associates degree so you can get a job that will reward your diligence.

No-contact to P. If you don't want to be involved with him anymore, tell him and stop contacting him. (AKA Block him on FB, screen his calls on your phone and don't meet up with him in person)