Sorry to hear your decision to divorce. I understand how hard it is on you. I really do. As a female i understand your wife even more. I read some people leaving what I think is really good advice. and some leaving some really bad advice. So i am not going to leave any personal advice. I just want to recomend #1 that you and your wife tell her doctor what is going on. Yes, you both need to talk to her Doctor. Talk to your wife ahead of time at a time when she is not flashing or moody. (there is a time) at a time like this with covid you may have to set up a phone visitation with her doctor. and make sure the doctor can hear both of your views on her condition (mood swings) your wife my not realize her actions.. #2 see a marriage councelor, dont throw away 20 years. again your wife may realize her actions and you may realize things you can do to help also.I'm divorcing my wife because of this menopause... She turned EVIL and I can't handle it. I tried suggesting she see her Dr but I nearly died from that conversation. She used to be the smartest woman I know but now she's border line moron at times. It's very sad but I just can't deal with her anymore. Almost made it to 20 years too.
#3. You may also be going through some changes that you dont realize. if your wife is going through changes your most likely are also. and deciding on divorce could be part of those changes. You may be in mid life mind set also. and inside of you, your having thoughts of being single and going out with other women again. more sex. etc. im not saying you are. im just throwing it out there that this is possible.
Im telling you this because i know, and i realized one day how i was reacting to my husband. and in my right state of mind. I told him. im sorry and thank you for putting up with me. but i get to where i cant stand you. i dont want you to look at me touch me, nor speak to me. its like i hate you more than anyone on this earth. But i knew it was not true. I did and still do love him so. Its just the change of life.
I did get some mild medication ( i will leave that up to your wifes doctor so not naming the prescription) but its very mild. and also our counselor recomended time apart. so my husband goes to his camp a lot and we have a lot of time apart. so i have my alone time, he also has realized he needed alone time.
and our conselor pointed out that i needed to give him his needs more often so i have gone to visit him at his camp (Booty call) and we are both loving it.
I see this passing. And i see us growing old together. but the change of life has been the hardest hurdle by far we have faced in our marriage.
Good luck whatever you decide. but please make sure the two of you have talked at a time your both in a good mindset and not beind controlled by the change of life mineset.