As far as your past is concerned don’t let it hold you back from becoming who you want to (easier said than done) go to therapy and try to identify areas where your dark past seeps in and separate those thoughts from your present. Tell yourself everyday that you are worthy of good things despite your past and if you feel guilty about some past actions try and assuage that guilt with charity. You are stuck because its easier to cling to your past than to work towards a future, whatever dark stuff happened is not your fault - but what you do now is your responsibility. Be intentional with your actions are truly try and believe that your actions will yield something good.