Going to have to completely and utterly disagree with this; nothing like a solid chunk of Just World Fallacy for the afternoon:
You don’t get laid unless you please a woman in some fashion. She has to approve of your appearance, smell, word skills, income bracket, etc. So the guy that gets laid a lot is, in real-world terms, the guy that serves a woman’s needs as the woman sees it. If you want to look at it from a strictly animalistic point of view, the guy that gets laid a lot isn’t so much an alpha male, but a stud animal. He was chosen for breeding because of his physical characteristics, no different than a horse or steer.
Alpha by any other name is still Alpha.
Also, Alpha Males are not Roided-Up Dude-Brahs who neg. They are confident, fit, and dominant individuals who lead by example.
And there are enough example of straight up Alpha Widow BS (this whole thread is a case in point) to point out that, while it may not be common, it is common enough to be considered.
Personally, I would not abide this situation, whatsoever.
Your wife needs to grieve, that is fine.
But what she is doing is beyond grieving; it is selfish, it is damaging your marriage, and it is communicating a level of disdain for you which is unacceptable.
It is time for you to take charge of this situation and lay down some ground rules.
Because the moment she begins involving a group of dysfunctional adults (who serve no purpose but to maintain her emotional connection to the ex-BF) which effect both your marriage and your daughter's life that is game over