why would someone care to delve into my past?

I didn't make a big deal out of it just got a restraining order against the guy, cut class and slept most of the day. I got sexually assaulted when I was younger than the age of consent, even the cop and da told me he was wrong without me going into detail. My question is why do his friends defend him and get shitty with me if it wouldn't have been a problem had he just let me break up with him? Not only did he assault and abuse me but he was violent, had a bad temper and cheated. When I told him I didn't want to see him anymore and he should go back to his ex he wouldn't leave me alone. The cop said he knew he was in the wrong by looking at the phone records and contents of his voicemails and texts.