Perhaps the conversation needs to go to a new level; e.g., "When I talk to you about my concerns, I feel like they get dismissed or excused away. It seems to me like my feelings aren't important." Also, some kind of agreement needs to be made regarding how many nights W spends each week with the other guy, and how many nights she spends each week with you. In addition, some kind of agreement needs to be made as far as a set time you and W will have a date night, be it once a week, once a month, or whatever.
Hopefully some of this will come out in counseling (with a mediator present). Hang in there.
Love means never having to say, "Put down that meat cleaver!"