Am I mistaken?

I think my husband may have FTD dementia. A little background: 5 or 6 years ago he started being different or inappropriate, especially in public, with waitresses and in stores. He became loud and way too familiar with strangers. We always thought it a bit bizarre as my husband has always been kind of quiet and patient. He started to become unmotivated. I chalked it up to him losing his business a few years before and encouraged him to see a therapist. He did and it helped a little. Years passed and I’ve been watching my husband become a different man. This past year has been awful. He’s full of anger and irritation, he yells and calls me vulgar names over something as minor as he didn’t like that I sighed. It feels like he is paranoid. He can’t make decisions or do something as minor as move a tv because it’s too overwhelming. He’s become very self centered, once calling during a power outage to scream at them that he needed his power repaired first because he was the most important of everyone. He blurts out profanity if we go anywhere. He forgets things that happened 5 minutes ago, but talks about childhood memories freely (something he never used to talk freely about with me). He seems to not comprehend time, i.e. he’ll say something about what we did yesterday when it was actually 3 days ago. He belittles and puts down family members and me often, but doesn’t understand why it’s hurtful or that we get upset. It’s like he doesn’t understand the emotional response of others. The other day he wanted to get his power tools and start dismantling things at a local business we went to because he was curious, then screamed at me for a 1/2 hour after because I said that wasn’t appropriate. Sometimes he gets quite sexually forward with me in public, it’s embarrassing. It’s bizarre. It’s like a nightmare roller coaster with no option to get off. I want to leave! He also has severe neuropathy and sees a neurologist who has done an MRI and nothing has ever been said about brain atrophy although these behavioral symptoms have not been brought up either. Husband has a neurologist appointment later this month to discuss these issues. He takes Gabapentin and husband thinks all this may be side effects, as he cries a lot too. I think maybe the drug is making something underlying worse, as he had these things long before he started Gabapentin. He knows something is wrong but I’m not sure he grasps the depth. Am I mistaken to think this may be Frontotemporal Degeneration and Dementia? He is only 52.