A weird dream about fiance's cousin...

So, a little backstory... when I was 16, and my fiancé's cousin was 20, we had a little fling and it was just that. We slept together a few times when we saw each other at parties. I hadn't met my fiancé yet and wouldn't for another year or so.

Flash forward to now, I'm 21 and engaged to my fiancé. We hang out with his cousin a lot and it's not awkward. My fiancé knows about what happened and he's accepted that it's the past and it happened before he knew me.

Now, on to the dream that I'll probably never be able to get out of my head.

Last night, I had two different dreams about him. The first was that we were hanging out with the cousin and his girlfriend and he wanted to have a threesome with me and her. She didn't want that so she shooed us away and told us she was going to play with herself and he cheated on her with me in the other room while she was doing that. Then I woke up.

The other dream was that my fiancé was cheating on me and we were going to follow him to see where he was going because he told us he was going to meet up with another girl. So we followed him and got lost and when we caught him, his cousin just held me and kissed me and told me I deserved better. I woke up shortly after that.

To be clear, I don't have feelings for my fiancé's cousin. I never have. I just needed a place to share the dreams because I thought they were weird as hell and didn't know who to tell.