how do i get my appetite back?!

Yep, been there.

You need to throw yourself into something else. Accept that you are grieving for starters. Allow yourself to be upset but recognise that you need something to immediately fill that void. Perhaps you have more time now for sport or fitness. That will get you eating. Or a night out with friends. Sometimes having a responsible social outing can really put things in perspective

Good Luck buddy. Love is a hell of a thing then one day you are happy and you find your soulmate lying next to you with the gentle cry of love's fruit crying in the nursery and you'll be so glad that your other relationships didn't work out.