For standing or throwing in the towel I'm torn. It seems that throwing it in after 4 months is craziness, on my part, who would do that so quickly BUT on the other hand he seems so determined, so self absorbed and sick, on a war path that I don't know if he'll ever come back from.
Whiterose, I think 4 months is too short, but only you can tell what is right for yourself. Compared to how long you've been married, to let it unravel so quickly doesn't make sense. Use the time on yourself to be mentally and emotionally, and in your case, maybe also financially ready to move on, if it comes to that.
About telling family members, Initially I had told my family about what was going on, but I soon saw that it wasn't helpful. I tell my parents almost nothing. I do talk to one sister, but only in general terms. No details. If you patch things up with you H, you don't want the relationship between him and the family poisoned by what you said to them, so that is one reason not to tell family.
