Oh OP, I was so sad to read your message. You write very articulately, even in a short post, and I think you are right that the experiences we have in our formative years can shape us to a great extent (especially in terms of our emotional responses to things).
This is not as serious as what you have been through, but growing up with a critical mother (she suffered from low self esteem herself, having been raised by a family that were not very good at covering up the fact she was a surprise baby) who fixates on physical appearance I have great difficulty even now (in my forties) accepting that I am slim, a healthy weight, not fat, quite athletic actually! I find it really weird looking at myself in a mirror, particularly if I can't see my face, as my body in no way matches how I think of it in my mind.
I've been married for nearly twenty years to a lovely man who is very complimentary about my body, I know my BMI is in the middle of the healthy zone, I can see myself in the mirror - and still, I can't get it into my head. Which was very rambly (apologies, have had wine!) but what I mean is it makes perfect sense that how you feel inside doesn't match the "on paper" version of your life. I completely understand that part of it, though I don't mean to belittle what you've been through.
Please don't suffer alone. If you feel suicidal then ring the Samaritans. They won't force you to do anything. In the longer term have a think about accessing some talking therapy, something like CBT which can help you to change your thoughts patterns or EMDR which is useful for processing trauma. You don't have to live the rest of your life feeling this way, you're not alone in having this sort of response to abuse (in fact, you're very normal!) and there are therapies that can help you to find a way past your early experiences. Merry Christmas to you.