You are (probably) a good person who deserves happiness. Do right by yourself, always.
It greatly helps to master the art of not giving a fuck. We all have a limited number to give, and you don't want to waste yours unnecessarily.
Know your priorities. Stay true to them. Everything falls into place from there.
When you feel stuck and there is a clear way out, no matter how difficult that path may be, start walking in that direction.
Listen to your body. It will tell you when enough is enough.
Life is messy and grey; people are fallible and complicated. So forgive yourself, for the past and for all the screw ups that lie ahead.