I'm not sure (continued)

Okay, so I have the screenshots of what my boyfriends ex girl's mom said. This is what she said:

But, I also have more pictures from last night... I feel like I'm a side hoe...

^^ that's him and his ex girlfriend.. I'm not okay with this.. But I don't want to tell my boyfriend that because I don't want him to leave me. We just started dating a week ago... I dont want thus to happen to me anymore.

I just don't want something like this to affect me again. I've already been cheated on by someone I've been with for a year... If that's going on I just wanna know now... I'm already depressed enough..