[Bethivy]

So just days before we got together (still seeing each other and sleeping together but not officially together) my boyfriend had a one night stand with another girl and about a month ago she had a baby and is claiming its his.
I need help in regards to, I am having a lot of trouble accepting the situation and I just don't know what to do.
Does anyone have any advice on how to deal with this situation, without a black and white, just break up with him. Because I do love him and I don't know if I feel I can leave him and live with my decision, but I also don't know if I can accept the child. Like I could if the mother wasn't around, but because she is, everything is much harder because I have mental health issues like depression and whenever he sees her and the child, my paranoia kicks in and I just lose it.