Most Helpful Guy
You are obligated to tell them nothing. Only tell them what you want them to know and be honest. You really have nothing to gain and stand to hurt yourself by telling people things about your past. What is the point? You can't change any of it and a lot of people will judge you and use it against you. And you are the one who gave them the info they needed to attack you.
Most Helpful Girl
Let sleeping dogs lie, @BreatheMe do not go barking up a tree with the Past that may not have been such a Blast. He doesn't Need to know every little bone of your skeletons that he may use to rattle his chains and yours.
Some things are left unsaid and buried And... Dead.
Good luck. xx