Afa, yes, going to the L is super tough. I know.
BUT, don't rush into telling too many people yet, and especially do not reveal that many details to the family unless she's moving out.

My H and I rushed to tell everyone as soon as he said he wanted a D (the first time) and he had already spoken with his family about how unhappy he was bc he was alone late at night. He had even shared the letter telling me he wanted a D with his 19-year old sister. BIG, big mistake.

The result?
1. In-laws saw me as the bad one...everyone sided with my H. The young sister has hated me since then.
2. Everyone saw our M as if it were over--even though we went through two more years of back and forth, which were totally awkward for everyone. We were seen as a weak couple, a troubled couple, and that didn't help the case. My H said the support from his family after that was gone.
3. When you guys reconcile (think you will) everyone will remember the details (if you reveal too much) and the relationships will not be the same.
So be careful with what you reveal. My H and I learned the hard way. For now, don't say anything unless she moves out. You can say you're separating. And then, if she files, you can tell them that. But nothing else. Trust me.
Hang in there.
Tori.