On the topic of custody you've said you will fight but what exactly would you be fighting for ...50/50 ...sole custody ? OR fighting against what you assume she want ...sole or 80/20 split ...see them on the weekend thing.
Giving her the benefit of the doubt, she could also be putting (gasp) herself in front of you and your marriage. As she should. Polyamory is part of who she is. If being with the girlfriend makes her happy, then doing things to keep the girlfriend in her life is part of putting herself first.
Isnt that at the heart of narcissism.
What kind of partnership/marriage is that? Which I guess is the base question Matt's having right now.
DO narcissists attract to one another? Does anyone know a couple in which both are narcissists?
And what kind of compromise can be can be reached if one spouse is always putting there need, wants, pleasure in front of their legally committed partner.