If I cared about my marriage I would avoid that couple completely.
Yes, it is.
No. That would be adultery.
If she is already married to someone else I would say it is time for you to move on.
when they have an affair with someone else
A film-director. She also divorced. She is now with someone else, but not married.
I would avoid this person.
In most countries, yes.
someone named somebody and someone else and also someone was there someone named somebody and someone else and also someone was there someone named somebody and someone else and also someone was there someone named somebody and someone else and also someone was there
Technically, yes. But if she/he's married to someone else, and you are there soul mate, then they have obviously with the wrong person, and only time, will reveal that to them.
yes
He has the same rights as any other father, the fact that he was married to someone else is irrelevant. But since you were not married he needs to establish paternity in court so he can petition for visitation or custody and also pay child support.
No, only use the word affair when married, if not married it would be called cheating.