Got cheated on and didn’t know until after the break up

Me and my girlfriend have been together for a year and a month. right and a month ago one day when she came over to hang out we were cuddling and watching this cake show on Netflix and I was super horny so I was kissing her neck cuddling her and she told me she didn’t wanna do anything right now because she hasn’t showered and I told her that I didn’t care and she kept asking “are you sure?” “But it’s dirty. I’ve been ovulating all day. It’s a mess down there.” And she kept making excuses and then she finally let me so I got on top of her, pulled her shirt up, starts sucking her tits to tease her to get her hot and and I was fingering her and she was extremely wet like never before and I honestly just thought it was because I was sucking her tits and I didn’t know she got turned on by that but long story short I kissed down her belly and took her sweats off and then her panties and it’s dark I can barely see anything and she tells me you’re gonna eat me out and I said yeah of course I would and she told me “you don’t want to do that it’s dirty” and I told her it’s fine and proceeded to eat her out and at first it taste different and I just thought it was because she was horny all day and she’s been working. I didn’t think much of it the more that I ate it the more juice was coming out, but I didn’t think much of it. I was turned on because I love eating my girl out and I ate everything out of her until she came long story short we had sex. I came on her stomach and a month later she breaks up with me and confesses that night she cheated and someone filled her up.. and tbh now I have a kink or fetish for that because it did taste good really wish she stayed but yk