For what reason would someone put their crazy, personal dramatic issues on Facebook?

On Facebook, one of my friends, (married with kids), put the details of a big fight she had with her husband. He came home, he said this, F him, she threw the wedding ring down the toilet, he is leaving now, me and the kids will be moving out, etc. I didn’t comment, but some of her friends sent hugs and said kind words. If I know her, this has happened a bunch of times in the past and things will be patched up shortly.

I can’t imagine why someone would put their crazy crap on Facebook like that.

I know nobody can be sure what this person’s specific reasoning is, but there may be some theories.

Can you help me understand what some possibilities could be?