It sounds like her moods are very erratic and she may be taking this out on everyone else. Many times when someone tries to manage mood problems the problem manifests itself through anger and resentment. It is very common for the person to not want to deal with their own problems. What she does is called externalizing - it's all everybody else's fault. Then she creates havoc wherever she can. She has to accept that she has some serious problems. I usually don't like ultimatums but you have tried being nice. You could arrange for a family meeting but she would have to be able to accept that she has a problem. I would introduce therapy in a way where she isn't the identified patient. Try marriage counseling and bring her into it as part of the problem.
You know what would serve as her wake up call. Don't be scared to use it. You need to give a consequence and be prepared to carry it out - not anything that you won't do! The key is for her to realize that it's not everyone else.
Please press accept; this is the only way I am compensated