Originally Posted by bean19
She has a LDR of her own, but her partner is not aware of her new relationship. This makes me doubt her ability to be open and communicative and i worry it will impact my relationship with my partner.
I am potentially interested in a relationship (primarily a friendship, but perhaps more) with the other woman, although I have some concerns there.
These are two red flags for me. The woman is cheating and I personally don't trust people who cannot be honest with their partners. I would be concerned for sure about this. Your partner is asking for a world of trouble if he is involved with someone who is lying. She could be lying to him too. When this other person finds out he might have to deal with a lot of fall out. For me its just not worth it... having been on that road.
The second one is also a red flag because it seems like sex in a threesome is a quick fix solution for something that is uncomfortable for you... I don't suggest going into this thinking that sex is the answer to all the emotional questions and insecurities you have... that might happen later after all that is sorted out, but the solution lies in communication and dealing with your own issues here. Not having another threesome. This kind of relationship dynamic is not like the ones you have had in the past with your partner, he has feelings for her beyond a fun fuck. Messing with that could potentially blow up in your face.
There is a lot written on this forum about all you are struggling with. A search in tags or looking at the stickies will bring up lots of threads and posts on jealousy... have a look and see what you find...
The number one thing for me with jealousy is that it is a fear/threat... it means that you are likely worried that your needs won't be getting met (closeness, time together etc.). If he is saying that this new love doesn't change anything for him, trust him; at least until you have reason not to... along with that, walk through your feelings and break them down to see what is really in there. Jealousy is made up of many emotions, not just one. See what you find and deal with one emotion at a time.