It's upsetting to know you are going through this. But from how I understand your post, you are aware of certain missteps on your part. And that seems like a good thing- you know what you need to correct. It would be difficult, of course, but you know where you need to start :)
Also, you may have made a "terrible mistake", but that does not make you a "terrible person". Our mind messes up that distinction but it is an important one!
Ifasinash
1
Acknowledging our mistakes is the first step to change. Take this chance to reflect on what you want your life to be like, who you want in your life and what you can do to make those relationships better. But first, learn to forgive yourself. Those who love you will see the changes you've made and they may find their way back to you.