Camelot, welcome to the Parent Emeritus forum. I'm so sorry about your stepson's situation.
I have a 26-year-old son as well---as you can read in my signature. Today, he is much better, but we have been down to the bottom with him, so I understand.
And, I'm sure you are in an even more difficult situation since he is your stepson.
The fact that he is 26 years old is both a good thing and a bad thing, I believe. He's an adult in the eyes of the world and the legal system, which means the consequences of his actions are more severe. He's an adult, so from a chronological age standpoint, it's past time for him to stand on his own two feet, whatever that looks like.
It is so frustrating and painful to watch someone with a diagnosed mental illness who will not comply with treatment. My son's girlfriend is again in jail for domestic assault (against my son). She is bipolar and is erratic with medication so situations never turn out well. I am hoping they are through this time, but who knows?
I don't know about you, but my heart goes out to her and to your son. But...beyond feeling empathy and sorrow, there is nothing more to do. If a person won't get the help that is available to them for their problem/illness/disorder/addiction, and in fact, they deny that the problem exists...there is nothing on earth that you and I can do to make them see more clearly and comply with treatment. I learned that the hard way, over years of trying.
His father asked him if he saw anything wrong with his actions, to which he replied, "I've got it all figured out". He is now asking for more money (it has been endless) and will not stay at a shelter.
Oh, yes they always have it figured out. They are going to do it THEIR WAY with OUR MONEY. That is where I believe the disconnect has to happen, and one of the first things to actually take action on, that ultimately may make a difference. Over time, as I learned, I stopped the flow of money. It took time for me to stop, because I love my son and I kept giving him chance after chance after chance. Finally, I realized nothing had changed, and in fact, I came to believe that my "help" was actually a big problem, for me and for him.
Once there, he refused to get a job. When he finally did, he was working 2 days a week and saw no problem with it. My husband just kept giving him money.
I understand this, your husband giving him money, even though his son wasn't pulling his own weight. We are terrified for them, and we think our money will help keep them alive. In the end, I came to believe that my money was actually going to end up being what would keep him in the same situation and unmotivated to change...because...why change if someone else is handling everything? You don't have to do a thing...somebody else will take care of it all.
How do we get him help? And do we keep sending money in the mean time?
Camelot, what is your husband, his father, willing to do? Is he willing to consider stopping the money? It is really hard to do without a lot of support. I recommend that you and your husband try some Al-Anon meetings in your community. They are free, and they are wonderful. You can sit and listen to other people who have been through exactly the same things, and have come out on the other side.
Second, you ask about getting him help. One thing that helped me was to have a list of resources that I could tell him about when he called and asked me for money, food, rides, etc. I learned to say no, over time, but I would share some of the list with him. I did it as much for myself as I did it for him, because it was hard for me to offer nothing.
Here is something I learned: People who are mentally ill are still responsible for their actions (unless they are psychotic and don't know fantasy from reality). That is a truth that a mental health professional taught me, and I was flabbergasted. I thought I should make allowances for someone who was clinically depressed, an alcoholic, a drug addict, whatever (all mental illnesses). I thought they couldn't help what they did. She set me straight on that. That was a good day for me, because I started thinking differently.
None of this is easy. My heart goes out to you and your husband. Don't expect overnight change from either one of yourselves. Go slowly and try to learn about detachment with love. There is a post on this forum about detachment at the top of the PE thread. Al-Anon teaches as well about detachment.
We are here for you and your husband. Please keep sharing. Warm hugs today.