Vent Away! That's what we're here for! We all need a place to go that is safe, where we can say what we feel, and not feel at risk of retribution.
Families always amaze me! The ones that should love and comfort us the most are usually the ones who inflict the most pain and damage. You didn't ask for an opinion, but please let me share -- your daughter is an adult, as is your future son-in-law. Your daughter's personality is pretty well formed by now and probably can't be changed unless she wants to and puts a tremendous effort into doing so. Therefore, the best, and simplest, course to take is to protect yourself. If that means having her move out, do so. Or telling her certain subjects are no longer open for discussion. Or asking your husband for much needed help. Best wishes for peace and quiet, and a good long nap!
Perhaps she has some issues of her own that need some coping strategies. I would suggest that she speak to a talk therapist and see if that helps. If there is anything more from there they notice they could make a referral. Complex as you have ever right to set boundaries but sometimes things are inherited so she might be coping with some of the same things we all are but only a psychiatrist could tell.