Some good advice there..
I'm pleased that you acknowledge your jealousy and obssession, that's a great start.
It will be difficult for you to find that "soul mate" in this cycle of pattern and each guy you'll ditch, or visa versa as either you will feel he doesn't love you enough, or he will feel closed in, can't breathe.
You need to start dreaming! Seeing things you want in your life, including hobbies, things you want to take up that you haven't...
It can't be all about, eating, sleeping, studying, boyfriend, and then all over again...
Start to get to know you.
There is a saying " if you don't love yourself, no one else is going to love you".
That doesn't mean "up yourself", just love being you, love you, then you'll look in the mirror and smile every day and become more assertive, instead of so needy...
Good luck.
CW