[M] I masturbated to watching my ex [F] fucking another guy

My ex and I have a really close relationship even though we aren’t dating so we kinda just stick together a lot and hang out a lot, although it’s a little difficult bc I still have a lot of feelings for her still even though we broke up 2 months ago. This happened like 2 days ago and still I don’t know what to feel about what has occurred, and I’m confused about weather I liked it or not so entirely I’m conflicted about myself now. Let me describe her to you, shes 5″0, great breasts,really small and tight waist,the softest sorta tan skin, latina,great thighs and a plump little butt. She is a great tease just by looking at her and her coy smile, it’ll make you feel like she’s going to jump on you at any moment.Anyway,we go to a small party with a couple of friends and then other people started coming along. We were smoking and drinking until then I see her getting really close to some other guy,he was some tall, ridiculously shredded guy and good looking guy too. They get really drunk and then she asks if she can use my room becasue my house is close to the party we were at and me being stupid allowed for it to happen. The thing is I was getting completely turned on and kinda sad at the same time even way before we got to my house I just don’t understand my feelings at all and I don’t know how to label it. They go upstairs into my attic and go to the room that had a couch in it, from downstairs I heard a lot of moving and and kissing it had my heart pounding and got me really horny. I opened the door to the attic and I started hearing more and more kissing and her moaning to his lips on her breasts and to her neck. I heard the belts drop and I knew then that this was happening and I was seeing her getting fucked missionary with her legs wrapped around the other guy and she was losing control of herself when she was clawing his back and biting his shoulder. Then she moved on top of him to ride him and the noises felt like ecstacy because I started messaging my dick as if it was involuntarily and it only made my heart pound quicker and it make cum so much faster. She then saw me looking and masturbating she didn’t stop or anything but only began to ride quicker on him and moan louder, I think she was getting turned on by it too. By the end of it he had came 3 times inside her and I was left feeling confused about my emotions. Even today thinking about it turns me on and I masturbate even thinking about it.
Honestly I need help figuring myself out,this post was just for me to vent out how I was feeling.