I'm sorry, but I missed the part where you agreed to this. I got that he informed you that
he was in love with someone else and it had already been going on for some time, presumably behind your back, since he only broke the news to you at that time.
I got the part where this up-until-recently secret girlfriend of less than 8 months at the time pushed her way into a family vacation via telephone so often that you had to ask her to please let your family enjoy their family vacation.
I got the part where you're apparently blaming yourself, saying you
threw a wrench in the works by making that phone call. Because it's your fault the two of them didn't bother telling THE wife that they
have now decided there's a 'co-wife?'
I'm getting all this about your husband and this woman deciding she will meet your son but not you.
I'm getting that the two of them will do anything they please, at whatever speed they please, with your son and without you.
I'm getting that you're agitated and upset over this whole situation.
But I didn't see where you agreed to this. If so, why did you agree to it? Out of fear of losing him? Because he was going to do it anyway?
Right now, it looks to me like a cheater and his girlfriend, too.