Boyfriend slept with my good friend...

Okay so, me and my boyfriend have an 8 month old son and have been together for almost 2 years now. We've been through some rough patches from mostly my doing and sometimes his. We have not cheated on each other. But we recently broke up due to conflict and during that breakup my friend and ex, at the time, slept together 4 times during the 2 weeks we want were broken up... Supposedly my friend broke it off the first time but then went back to have sex with him, and finally my ex broke it off bc he wanted me back and he even told her that. And the crazy thing is that I blocked my friend before me even knowing about her and my ex having sex bc I thought she was fake and I've had reasons before finding this extra bs out... Lmao and then she contacted me wondering why I did and asking how she was fake and was trying so hard to convince me on how she wasn't... Well after her doing all that I forgive her, so we're cool and good. And I'm over here talking about my ex to her trusting her and she's acting so normal while they had already had sex a handful of times. Oh, and another thing is that my friend had sex with her boyfriends best friend my ex, his best friends girl... So it was a messy situation. Well after my boyfriend trying to get back with me I finally take him back after him begging bc at first I didn't want him back, but I do love him and I want us to be a family... Anyways, I lived in GA with my boyfriend and after the break up I moved to Florida to live near my dad. So he was staying in Ga for a week till he moved here to be with me and my son. There was a hurricane that hit Ga and during the hurricane, he was drinking with his buds at his house (lol no he didn't evacuate) but come to find out my friend texted him asking for her bf who was his best friend and they ended up texting about having sex again... My friend is a slut and I already knew this but I didn't think she'd be the type of slut to do something like this. My ex was a shitty bf to all his ex's before he met me, cheated on basically all of them. But hasn't on me yet and trust me I would know. I find out everything he had or has or is doing. I'm that girlfriend lmao. But after finding out they were texting about having sex again throws me off, I mean it never happen bc they just talked about it and the next day he moved here to Florida. And I didn't find all this out till he got here, and I found out by my friend bc her boyfriend  found out from one of her friends so the only reason she told me was bc she was caught and I lowkey feel like she wanted me to dump my boyfriend so she could sleep with him some more and she was actually a little disappointed I didn't, obv I more then likely would not of taken him back had I found out while he was still in Georiga. But that wasn't the case, so he begs for forgiveness and blocks her on his cell and all social medias. I forgave him but everyday after that I constantly brought it up bc I was so pissed he'd be so low to do that to me. I'm not gonna lie... Lol I wanted to fight her, trashy I know, but y'all don't understand how pissed I was. Personally I wanted to fight him too 😂 but after a week or 2 now things have cooled of between he and I and we're doing better now. He's working his ass off at my dads dealership as a detailer. He says he regrets doing it. But I feel insecure now... Like I'm not enough for him, or good enough for him, to go and hunch one of my good friends. Like if he really loved me how could he something like that? Honestly I feel like that hurt me more then if he cheated on me... I hate the girl, I'm hurt by her also. But she doesn't matter anymore. I just want to be happy with him... I feel weird sometimes having sex with him knowing my friend had her whorish mouth and vagina on his penis and knowing he enjoyed it... This girl has had like 12 sex partners and I, only 4... So I'm not as experienced. I just don't know how to get over the situation or how to not feel like make myself feel better about it. I have gotten over it some so I'm thinking it all has to do with time. Just some advice on the whole situation would be awesome. We do love each other and our son. We were broken up while it happen so I guess whatever he does when we aren't together isn't my business, but damn really my good friend? Your best friends girl...  Also so let me mention that this is suppose to be our new leaf from all the bs that we have caused each other... But I agreed to a new leaf before finding out him sleeping w my friend. Input plz 🙄