I'd say all of this happened - no proof but I wanted to give some insight:
I am a mental health clinician (social worker) who does mental health assessments to provide provisional diagnosis and place folks into the right treatments.
The thing with Rose McGowan is after she went public with her story of sexual assault & abuse in Hollywood we saw a woman who was reliving and re-experiencing trauma
in public. I think we could all see how distressing this was for Rose. I really empathize with her because trauma can do some pretty intense things. Rose was brave and spoke her truth about many folks in the industry. I am not disputing any of this as it is her experience and she went through hell and then had to relive it in public.
Rose feels that Alyssa is somehow complacent with issues in the industry due to her husband being a talent agent/manager at an organization Rose takes issue with. I do think this is a bit unfair. To me, this is like a vegan taking issue with the manager of a McDonalds - everyone needs to work and people do what they have to. Rose didn't ever say anything personally about Alyssa's partner being a bad guy. Rose also takes issue with Alyssa's involvement in the "me too" movement because Alyssa did not create the movement but became the face of it. Alyssa herself always states that the tweet she re-tweeted that went viral was in fact from another (non famous) woman. However, obviously being retweeted by a huge star gave the movement more public awareness - I don't feel Alyssa takes credit for the movement and only takes credit for helping her support it.
In terms of the things from the past and Alyssa's diva behavior on set, or how Alyssa "made life hell" for Rose on set - I'm not sure what to think. I am sure Alyssa had some bad days at work like all of us. I definitely get cranky from time to time and I only work 37.5 hours a week. The actors and crew had to work 12 hour days.
I think Rose only brought up the things from the past with Alyssa on the set of Charmed to give her more leverage the negative things she was saying about Alyssa. I think Rose felt by personally attacking her in this way it would help people believe Alyssa was somehow a bad person. Roses' accusations about Alyssa's on-set behavior came out of a political discussion the two women were having on twitter about the democratic party. When Rose couldn't find anything to say politically she came for Alyssa personally. Rose also has a pattern of doing this - Rose had negative things to say about Meryl Streep after Meryl wore black to the Golden Globes in a silent protest against sexual abuse. Rose told Meryl on twitter that her silence was the problem. Meryl defended herself and said she was not aware of Weinstein's assaults when she worked with him. Again, I think it is unfair to take issue with a woman like Meryl who acted in films produced by him/his company.
This all being said, I think Alyssa understands what Rose is/has went through and that's why she has stayed pretty gracious on social media. All Alyssa has really said when asked is that she doesn't speak to Rose because she has been hurtful towards her and her family but that she still loves her and wishes her healing. And this is completely fair to me, especially when Alyssa has young children who could be impacted by the negative things Rose said about Alyssa/ her husband.
I do like analyzing the dynamics between the stars present day, but do genuinely wish it would stop.
If you don't like someone leave them alone. Even moreso, keep things off social media. I am grateful that Holly/Alyssa have both stayed pretty neutral in the public eye regarding this stuff.
This turned into quote a rant - apologies (haha).