Throwaway because people involved may know my Reddit, although if they’re going to find this they’re going to find this, and I’m sorry I went to Reddit instead of talking to y’all? I just need an outside perspective on everything.

So this is going to be a very weird and long post, and honestly I don’t even know what community/sub I should be posting this in, so if people have better suggestions that would be great.

Me and my partner (both 21NB) have been together for about 2.5 years, and have been strictly monogamous that whole time. We’ve had theoretical conversations about a third, but up to this point have agreed to be monogamous due to concerns with jealousy/possessiveness and past issues with codependency that we needed to work through. We currently still are monogamous, and despite what I’m about to type out, I would like to remain that way (because it works for us personally and to my knowledge that is also what my partner wants).

This weekend, however, I had a weird experience and I can’t stop thinking about it. There was a party happening at Partner’s house (really it was just our friend group getting together) and most of us, including me and Partner, were drinking. Important to this story however is DD (20F) who was not drinking, because she was the designated driver.

Now when I drink, I tend to not like to be touched, as it makes me sleepy and if I’m drinking I want to be awake and have a good time, not fall asleep. I am also in general not the touchiest of people, although I tend to make exceptions for my partner. So at one point in the night me, Partner, and DD are all sitting on the floor in that arrangement. Partner tries to touch me (like run fingers through my hair), however I am not really wanting that and tell them as such. They oblige and stop touching me. A few minutes later I turn and look and DD has her head on Partner's shoulder and (fairly loosely) has her arm around Partner's shoulders. I would say that in general both me and partner are closest to DD out of all other people in the friend group, and Partner and DD have some additional interests that overlap, and classes as well (we are all college students).

When I saw this, my immediate reaction was not jealousy at all, but instead "oh my god, that's so cute, oh I'm so happy Partner has someone touching them because they really love that!" There was also a bit of joy? happiness? positive feelings about it being DD specifically, since like I said, she is who we are closest too. (I also have a personal suspicion that DD is sometimes lonely, but that could be me reading into things that aren't there.)

There is a running joke in our friend group that as long as it's platonic, I don't care what my partner gets up to (obviously everyone knows this is a joke and I would actually in fact probably care if they had sex with someone else). So it's not like DD had to ask, as cuddling is actually something I have 100% cleared as okay with my partner to do with other people in all seriousness.

That night, after everyone had left but while still intoxicated, me and my partner talked about it and I expressed these happy feelings and Partner expressed that they enjoyed it too (and agreed with my suspicion that DD may sometimes be lonely). They also told me that at some point while I was occupied with something else, they ran their fingers through DD's hair for a while and she seemed to really appreciate that. This only amplified the feelings I was having. I figured that that would be the end of it, and I would wake up with happy memories but be able to move on as normal.

That has not been the case. I have now been thinking about it for days. At first I talked it through with another person unrelated to everyone involved, who told me about compersion, and all of a sudden it clicked. That was definitely the word to describe what I was feeling (have been feeling?). But even with that knowledge I haven't been able to stop thinking about it. Not like in a bad way, it's not like it's causing me angst that I'm happy my partner was happy. It's more that I can't stop thinking about wanting to feel it again?

Like I keep thinking of scenarios where Partner and DD are hanging out (with other people/me or just them) and they are cuddled together or doing some other activity and are just happy and then I know that so then I feel the compersion again fresh/new? None (well, basically none) are sexual in nature, it's mostly completely platonic situations my brain is putting them in. Any that aren't I chalk up to my usual (diagnosed) intrusive thoughts taking a different turn than usual. I've never had this happen before with another friend and Partner.

Does this go away? Am I going to move on to a point where my brain is not in an obsessive loop about this? Generally speaking I let my intrusive thoughts run all the way through and then they leave and are gone, but in this case letting these thoughts run through is just causing more to occur.

I want it to go away mainly because I feel weird putting a friend into fictional scenarios in my head, especially because I’m not sure about DD’s exact sexuality (I know she identifies as aro). I also don't know how to bring this up to Partner without seeming very weird/creepy that I have continued to think about it when I am almost certain Partner has moved on.

I do have a therapist, and under pretty much any other circumstances I would bring this to her, but this is such a weird and specific situation I don’t know if that would be the best option (mainly because I’m looking for advice from people who “get it” and I know she wouldn’t).

Thanks for any advice y’all have. I really appreciate it.

TL;DR: experienced compersion for the first time in a platonic setting between my partner (were monogamous) and a friend, stuck in mental loops about it, don’t know how to make them stop