My wife betrayed my trust and doesn't value my feelings

That is cheating! An emotional affair bordering past that. I am so sorry. I am dealing with feeling betrayed apparently I am just irrational and over reacting. I would try a marriage counsellor. She needs to see that this type of behaviour is inappropriate and that she is hurting you and betraying your trust. If your partner would be hurt by the conversation you shouldn't be talking to the person. When you marry someone it's not just the physical you are giving to them, it's your heart, your mind all of you. You aren't mean to share this much with anyone other than your husband or wife. Again I am so so sorry for you and that you are being made out to be the bad guy. You aren't just like I know I'm not.

1st, please understand that anyone who knows me will tell you that I am brutally honest and give advice that is completely in line with that same honesty, so forgive me for this...

She does not respect you (or the child) and you should kick her out or leave her... Her behaviour is befitting a fetish-hooker and is far from lady like. She clearly gets a kick out of all this too and couldn't be bothered about your feelings or how her actions affect others.
I stand to be corrected, but you come across as a well-mannered, soft-stolen and gentle kind of soul. In my experience, women tend to take advantage of a man when they know he is committed. The boundaries are pushed and risks are taken. It is not too dissimilar to gambling...

My advice (again, sorry for the honesty) is to man-up and stand up for yourself, when this kind of thing starts it is unlikely to stop.

I am sorry that you are going through this, but the solutions are never as vague as they appear.

LDS means the Church of Latter-Day Saints, otherwise known as, the Mormon Church.