Keppra STOLE my Husband- the drug from HELL and a VERY irresponsible neurologist

Where do I begin? I met my husband in 2006. He had experienced his first seizure 2 years before and had been prescribed Dilantin. We dated for three years and then got married- we were both 29. He was always so jovial, was up for anything- loved being around people, going out etc. He had his second seizure in 2008 a few hours after we landed in Boston after taking a red eye from San Francisco. Unbeknownst to me, he had taken himself off the Dilantin....As a result he was again prescribed Dilantin after an afternoon spent in the ER. Fast forward several years- his Neurologist retired and he makes an appt. with a new one. This new Neurologist tells him that he's been on Dilantin too long and it might end up screwing with his gums. He prescribes him KEPPRA. Tells my husband "let your wife know that you may become a bit irritable at first but that should level out". He certainly became more irritable. It wasn't unbearable- just noticeable. As the months continued so did his irritability and now, agitation. I didn't say anything to him. I was afraid that he would stop the meds cold turkey and end up having a seizure while driving our 2 children to school.... It's now been at least 3.5 years of Keppra. The last at least 3 years have been HELL. I no longer know this person I'm married to. He's mean. He's SO critical of me and our children. His mood swings are out of control and the kids are scared. He is extremely combative- argues over EVERYTHING- mostly little silly things!! He is clearly VERY depressed and full of anxiety- he never wants to do anything (except ski). No longer golfs, doesn't want to go out to dinner, etc. Everyone annoys him and he says that "we don't think the same way". We will pull out of my parent's drive way after a day at the pool with my parents, siblings, and nieces and he will literally criticize each and every family member the entire drive home (while also criticizing my driving- too fast, too slow, wrong lane, not stopping at stop sign long enough, not pulling up to the stop sign enough- or too far, wrong/ preferred route home etc.) He once completely flipped out at me for buying two kinds of milk at the same time.....(almond and oat). Our sex life has deteriorated. It was subtle at first. He stopped initiating. Then he couldn't maintain an erection. Then he started asking for a threesome......told me I was "too vanilla" and that I needed to see a sex therapist. He has lost SO much of his hair. There were days that I would find SO much hair on his pillow case..... His energy is low- all the time. He literally has no emotion and no empathy. He says we have no chemistry and that he no longer feels anything for me. He says holding my hand is like holding his sisters hand. I've just learned that he hasn't seen his neurologist in over 3 years. This neurologist has continued to refill his prescription. I have called this Doctor's office 3 times. 3 TIMES!!!!! They refuse to help me because I'm not power of attorney…. So now I'm in therapy, my two kids are in therapy (ages 9 and 11). And as soon as this COVID-19 shelter in place is lifted, my husband is moving out and we are divorcing. WHAT THE HELL HAPPENED?!! Where did the person I married go?!