Any advice for being scared that people will abandon me?

Know your worth. Love the heck out of yourself. Know if someone leaves you, its their fault.

Let me tell you a story: He once was a person who liked morbid things and was abandoned in his time(s) of need. He never really got over his heartbreak(s), and now 5 1/2 years into a relationship; he still needs to be reassured by the man he loves that he still wants him, that he will not leave him, will not just give up, and will be there for as long as he is alive/or until they mutually break up.

Moral of the story: It doesn't go away because we wish it, it takes hard work to keep both feet on the ground. You learn to cope, to find an outlet to the stress and issues that you have. Maybe by painting, drawing, video games, read a favorite book over again (it adds a sense of comfortablity by adding something familar), yoga, swimming, running, meditating, and maybe you could write your story out. I am 25 years old and I still have abandonment issues. Be safe darling.