Do you ever get over it

I reached to this group or forum because I feel like I have no one else I can talk to in confidence thay I can get an unbiased truth from. My boyfriend and I have been together for 2 years and 8 months we have been thru plenty of ups and downs but being cheated on affected me worse than I thought it ever would and I don't know have I fully gotten over it even though we have moved on past the situation. This chick was relentless at trying to make me mad even though he refused to leave me for her or actually admit and acknowledge the fact he had anyrhany to do with her. We have had several altercations but none physical because she has always ran away or sent messages via social media but honestly she's really a coward in my book. So recently she just had a baby so she aftualla got pregnant round the time all this was going on and instantly I thought this was his baby so I have been in a blind silent rage every since. I evem made vim prove to me that it wasn't his baby by him asking her and she said no and of course that's still not enough for me and I don't believe her because she has lied for him before and she's really delusional when it comes to him so now I'm at the point where I'm confused on how I feel and what to do because if she is lying and this really is his baby I'm done. But will I ever find out or know the real truth and my biggest fear is that they are gonna keep it a secret and sneak around with him seeing her and the child and I find out later on down the line.