Hi Til, sorry for what brings you here but glad you found SR. That is quite a serious situation, I can understand your concern(s).
I do have some thoughts about the K3, but first, someone said in another forum today - that being in this type of relationship can mean not seeing how dysfunctional it is and nowhere near normal (paraphrasing). Isn't that the truth.
How can you know, at this point, if there can even be therapy and healing of your marriage further down the road. Honestly you don't know him all that well at this point, he has been in jail a long time, he has no doubt changed from the person you knew and I think his current behaviour shows you who he is now.
Is that a man you want to be married to? Do you want to leave your friends and family for him?
I understand that you have been planning this for a very long time, working toward it, spending money on it, but none of those things is worth your wellbeing.
The K3 for instance (which has about the same processing time as an IR1, so not sure why this was even suggested), I hope you have saved a lot of money if you do go ahead with this as you won't be able to work immediately. The only person you have is a heroin/meth head who is living in a sleazy motel with a fellow addict he just met. Hmm.
So what I would do, personally, is put the brakes on the whole thing, immediately. Don't worry about the visa, don't worry about him, only look after yourself. You need to protect yourself from this and him, honestly. Think of it this way, say you were walking downtown in your city today and a guy staggered out of a hotel, completely stoned and a mess with an equally stoned woman on his arm. If he came up to you and asked you for a kiss - how would you react (I hope you would run) - THAT is the truth of what you would be walking in to, not the dream that you had or have.
It's sad! You have waited many years for this but omg you deserve so much better than this. How you could ever hope to get him cleaned up enough to attend the immigration interview, I have no idea.
You didn't Cause it, can't Control it and can't Cure it (the 3 c's). Focus on yourself, what you want in your life, surround yourself with people that love and care about you.