I do not know if you want me to broadcast this in public, but I know exactly how you feel. After all, I watched your relationship unfold as it progressed. It started out as the perfect dream, but it developed into a nightmare.
I do not like to blame the victim, but you played a big part in how he turned out. You had the power to influence him for good, but you chose to do nothing. You were afraid that it would damage the already fragile fabric of your relationship. You were intimidated by the prospect that he would somehow hurt you. Worse, that he would somehow leave you.
Do you remember when you washed your metaphoric hands from one of his terrible decisions? How did that turn out? Nobody had sympathy for you. Everyone else saw it as guilty by association. You saying that you had "no part in it" did not convince anyone. In fact, it drew more criticism because you are one of those closest to him.
Sometimes, when you fear the most is when you have to do the right thing. You worry because you care. At the very least, you know you could not live without him. Turning a blind eye not only DOES NOT solve your problem, but it allows him to continue on the path of destruction.
What would happen to you then?
I have seen him speaking in riddles, wild promises of grandeur. You think it is bad that he treats you like an object right now? What if somewhere down the road, you are nothing to him?
What would you do then?
Would you live with the regret of doing nothing when you could? Or, would you live with the regret of not leaving while you could?
Choose carefully because you are running out of time, and this is not me trying to scare you. Each day of inaction means an increase of disfavor for you.
Should the flames between you two die out, do it for self-preservation.