I’ll piggy back on your comment, I was gonna say something similar (and I fully agree with it 😊)

With only the information you provided, it sounds like you’re potentially navigating some high functioning depression, maybe some meaninglessness. They can go hand in hand, and much of the joy of life is lost when/if you’re depressed with no personally meaningful direction.

Therapy is a good starting point, or even just some gentle self analysis of what may have led you to these feelings (as opposed to the symptoms of it, which it looks to me like what you described).

It’s a process, and it can take a very long time to learn how to be gentle enough to listen to yourself without judgement. So in addition to therapy, I’d add meditation to allow yourself space and journaling with personally directed questions (e.g., what do I feel, what may have led me to feel this way) that might grant you insights. Dig for what means something to you, and find a way to make it your reality.

One final thought - do try getting out there and connecting. It’s hard, irritating, and exhausting. But sometimes we spend so much time in our own space/heads that we ruminate ourselves into a quagmire. Ppl and activities corner that rumination to fewer hours of the day, and gives us a break from our own thoughts.

As poster above said, you’re not even 40 - lots of years of beauty, hope and meaning to be found and loved, though it can take time to really get there :)

All the best, OP

Dude!

In my opinion, as a default, ENM is a harder version of relationships. Some individuals may say they’re fine with it so that they get to be with the person they like, but when the rubber hits the road, they are not - cue jealousy.

Without further info, what I think I’m seeing here is J now has to decide if he’s okay with real ENM. And K has to decide if she’s truly ENM, likes one of you more, or is monogamous and telling herself she’s not (based on her decreased availability to OP). I agree with another comment that communication is absolutely key here, esp. if she wants to continue seeing both of you.

My guess is J will tap out or push K to cut OP out. If it comes to that, she may pick J due to longer commitment. But as my GF says - if you cheat, go with the new blood - if you were happy you wouldn’t have needed another.

Note/food for thought: my personal stance on ENM is that it’s less of a long-term solution than it is the dating version of FWB. No hate, I just don’t think on average it pans out better than FWB without extremely (read: beyond the average person’s) good communication and empathy. /endramble