I thonk you cannot say until you are there.
There may be other factors to consider... children, circumstances.

A relationship needs to be worked on and if someone chooses to stay in such a relationship and work on it then respect to them.

People make mistakes you know.

Sometimes when people make these threads, and they aren't in relationships nor dealing with a cheater, it can mean they are struggling with the helplessness of watching someone they care/ed about settle for less than love. And at times it is because they idealize love and hold it as a virtue, the realization that there are those who do not experience love the same way, and would often take advantage of such trust, creates uncomfortable fears. To love is to be vulnerable. The whole thing is akin to vicarious trauma.

I know a few marriages in which the husband cheated, the couple went in for counselling, and gradually over time trust was restored. The marriage ended up far healthier than it had been beforehand.

But it is hard, painful work.

And there is a woman who comes and goes on SW who has posted about how she has not only forgiven her husband for his affair, but that the teenage son (probably an adult now) from that affair is welcome at family gatherings.

Forgiveness is a powerful thing.

IDK, I might. Saying something and doing it can be different things. I would have to be in the situation to determine that.

I understand. My ex-wife cheated on me, probably several times, before I threw her out and filed for divorce. She tried everything she could to come back to me for a year or so. I did miss her terribly but I just couldn't forgive her or trust her again. Her betrayal just hurt too much and I could not feace that again.

I took back a cheating ex after they cheated many many times

Sure. I've cheated and been taken back so it's only fair

the thought of having sex with her after someone else has been there. No i could not take her back