Possible red flags in my current relationship
Hi there I'm 31 (m) with a 28 (f) originally together for 10 years, married for 5 years and have a 18 month old child. My wife recently found a dominant she enjoys the intimacy and kinky conversations with which I don't mind. Lately though, my wife has begun to have more argumentative starts to every if not every other morning. I've been emotionally exhausted for quite some time for many reasons and haven't felt true intimacy from her and she mainly comes to me to try to satisfy the horny cravings of the other partner.
Also the partner my wife is currently seeing won't inform their current female partner of their relationship because they don't like poly and are insecure (so in this case my wife is in the mistress role right now and it's almost reached a 3 month mark) which is a red flag on its own.
Me and my wife's intimacy was damaged before this partner also entered but we were trying to work on it and were actually developing intimacy again. She also has BPD and DIDS and seems to have attached to the new partner like an FP yet he's long distance and she's becoming overtly reliant on him and makes me feel like I'm just supposed to provide and degrades me for not even doing that enough. We have been struggling for years based off both her committed choices and a few of my own along with me carrying the majority of the weight the best I can.
I'm getting to the point I am considering divorce when I never thought I would. I'd like some perspectives on this/others view on this situation. I am not against poly but I'm against toxic poly/boundless relationships.