He is awful personality wise and is being ripped off financially. He changes his moods which result in an ongoing circle. He is not accepted socially anymore and is being ripped off with contractors, siding men, friends, family. Then the next minute he seems to know what he is talking about and gets angry with these people even me for taking advantage of him. Then he's back to the other behavior. So I have to deal with people he makes contracts with and then doesn't want to pay them. He gets lost coming home and is afraid to eat my cooking or anybody else's, he lives on buttered rolls and pizza. I've spoken to his doctor who says he is getting worse but he doesn't think it's Alzheimer's.
It sounds like he needs a full work up as Barb & Ahmnijoy have suggested. Not his current doctor but a gerontologist affiliated with a health science center that has a teaching hospital. It’s not going to be a single MD diagnosis but several to determine what’s askew in his brain.
Id suggest you run a credit report from the big 3 on you all as a couple and on his business if he has one. Also try to go online to courthouse property records to see if any workman’s liens placed on your home, & if so, you can get a download copy for a few dollars. If things are amiss, open a bank account only in your name at a new bank and start putting $ into it in amounts he won’t likely notice. Even a few hundred set aside will give you a bit of a sense of control should there be an emergency.
If his state of mind has placed you in jeopardy, you can use this info to discuss with the new MDs to get a letter of incompetence on him so a guardianship can happen. If your not able to override him then someone else in your family can be the guardian.
You may may want to do a diary as to his behavior as there may be a pattern. Plus diaries can give you a sense of doing something with a situation that’s kinds out of your control.
You really need to get him to the neurologist for evaluation. You know this behavior is not normal. People with even the beginning stages of dementia can be paranoid and delusional. My mom was. It’s how I knew she had to be evaluated. Who said he had Alzheimer’s 18 years ago? Was he evaluated by a neurological team or was his doctor guessing this is what it was? If it’s not Alzheimer’s/dementia, he may need scans for a brain tumor. Doing nothing is not an option. He needs help and he needs you to get it for him.
If he is in contact with tradesman, someone has to supervise him. He is not able to handle these transactions and cannot continue doing so. I would absolutely avoid the so-called “friends” and the family who are taking advantage of him. If you do not already have Durable Power of Attorney for him, get it now before he is declared incompetent and take control of the finances.