Are you jotting down the dates for the bad times? Are they, by chance, coming around every 3-4 weeks? Have you tried giving her chocolate?
Were that the case this wouldn't really be an issue.
Had a minor blow out this morning. A year ago my car burnt in a fire...oddly enough due to a domestic dispute someone else had. Girl was cheating on her b/f so he lit her car on fire while parked next to mine. We decided to just go down to one car to save on money since she rids transit to work anyway. Worked well until now and she refuses to let me use the car, which fine, whatever. Her parents knew what was going on and I go sign paper work on a car today so they said I could use theirs. My job requires me to drive to meet clients and I have a meeting today with a large account holder, which I had to cancel on once due to issues with the wife. I was told regardless of my performance that if it happened again I shouldn't come back to work.
Well this morning she found out her parents said I could use their car and she flipped, found their keys they had given me and took their keys and then her car.I calmly asked her to turn around and she told me she went to a park and ride and good luck finding the car. I informed her I would lose my job she said maybe I should talk to her parents since they chose me over her. I told her they chose me having a job on account that's whats best for our son.
After playing this game for a few moments I realized she uses her cell a lot for work and told her I didn't want to but if I needed to I would shut her phone off since it's in my name and I pay for it. She told me she needs it for work and I just didn't respond and let her think on it a moment and then she told me where the park and ride was and said to have it back by 5:30 and hung up.
The car thing was literally the only piece of stress I had right now and that'll be gone this afternoon. Her ranting, raging, screaming I don't sweat. When she got home last night she was throwing stuff around (keys on table and purse on chair) and stomped through the place but once our son got home shortly after she was civil and that's all that matters really for the moment. It bothers her a great deal that I don't get bothered, she will try to drag my son to her room with her to hang out in there and he'll say no he wants to stay out there with me....stuff like this;
Her: -insert sons name here- come to the bedroom with mommy and we'll watch some TV
Son: No, I don't think so...I think I'll stay out with Daddy and play.
Her: But mommy will go to bed soon, you have to come tuck her in and daddy will just want to be on the computer anyway. (her idea of a jab at me because she gets mad all I do is sit on the computer after everyone is in bed...like it matters)
Son: But I don't want mommy to go to bed, mommy needs to stay out here. (tugs at my heart strings)
Her: Please?
Me: Hey buddy, why don't you go tuck mommy in and cuddle with her for a few then we can feed the cats after.
Son: OKAY! (he loves helping me feed the cats)
She'll look at me with a mix of anger, annoyance and a hint of appreciation (I know the look, it's been there for years and we've talked about it during her good moments). I can remain civil for as long as I need, stuff typically doesn't bother me and I don't get ruffled by things that are out of my control. Her issues are out of my control so I refuse to let them bother me. If I did I would have been a broken man long ago.
Anyway, I go meet about my car soon so that will take care of #1 on my list. All is well so far.