backbreaker, much love and respect for being so candid and also establishing clear boundaries, even if I don't agree with them.
I will say this much, within the circle of marriage, new friends of the opposite sex will always be viewed as a potential threat. The best way to deflect said threat is to establish the fact that your woman is still #1. Let's be real here, you can buy her all the gifts in the world, but your most valuable asset will always be your time. If you invest more of it in someone new, while taking your current lady for granted, she will feel "cheated on" - I know that's harsh because you not even fukkin this ho, but it's inevitable. In a sense you are choosing your friend over the mother of your children when it comes to the currency of your time, and that hurts no matter how you try to sugarcoat it.
Regarding your latest spat, I'd say you were a bit uptight. Maybe I am just trash myself but I see nothing wrong with adults wanting to have a drink at a kids party. Sh-t, my kids are the reason I drink, lol! Of course if the ho gets out of line you can ask her to leave, but preemptively harshing one's mellow like that is generally perceived as the mark of someone with a huge stick up their ass.