A players character has spent their childhood in brothel and it is bothering me. What can I do?

The players character spent their childhood in a brothel before being sold to pirates and being a crewmate before deciding to retire and get married only to have their wife killed. The player himself is rather edgy and threatens PvP from time to time and being edgy assholes seems to be his trend since the other two characters of him I have seen are edgy assholes as well.

I joined the gaming group three weeks ago(They were playing three games and I got to join all three.) so I don’t feel comfortable complaining about it. He is the argumentative sort saying how his character being an asshole is the fault of the entire party rebuffing him(He is rebuffed because he’s an asshole rather than the other way around.) after every session and going as far as to say that his character could start PvP.

I am both new to the group and not in the state of mind where I can deal with that kind of person(Social isolation and exams taking their toll from my mental state.) so I don’t know how to prevent him bringing up his characters past as it is bothering me since it involves a child in a brothel.

What can I do in this case?Should I go talk to the GM or other players? Should I just refuse to acknowledge him?