difficult child problems are not going anywhere, and NOTHING done now will accomplish anything that won't be accomplished next week. Nothing positive anyway.
in my opinion you are an angel about your mom, just saying. I hope deep down she knows how great she has it with a daughter like you!
I hope you follow through with no more support for him. If you are on his lease for an apartment, try to sublet it. don't allow him to live at home and do nothing. Consider what my mother told my brother at on point, and told me about a specific job: "If you want to live on a $7 hr job, feel free. Go and live it in your own place. In my home you are living on two combined salaries of professionals who are established in their own careers. You are welcome to stay if you are in school and getting good grades and working, but otherwise, you are always welcome to visit." I was told this in regards to delivering pizza for a restaurant I did other positions at after a driver for another pizza place was murdered. Bro was told this after two semesters of astoundingly low grades in very easy classes and while not working regularly and partying quite a lot. He also was refusing to follow ANY house rules including very basic ones like flushing the toilet after each use (he claimed it wasted too much water so he only flushed once a day in his bathroom - yuck!)
I firmly believe that ANY parent who is paying for a child's college or further education should insist that the child give them unfettered access to their grades and bursar account. We didn't have online access when I was in college, but if my folks wanted to see something, they saw it. Period. Refusal would have meant that their support stopped until they saw it. It was not spelled out, but it was clearly expected. My kids know that it will be expected of them, also. I don't just mean tuition and fees were stopped, ALL support for dorm, apt, spending, food, etc... were stopped. It was part of the bargain,and a SMALL thing to expect at that. At any time in the future that you agree to pay for school, this should be part of the contract.
I am sorry he is pulling this koi. Make sure you remove a part or two from the suburban when you park it, otherwise he is likely to get a ride and 'borrow' it. At this point, given his lies and behavior, if he takes it again you should report it stolen. I know that will be very very hard, but he NEEDS these consequences if he is to EVER get the message that he cannot continue this behavior. Otherwise the consquences will be given by others much later and he will likely have a HUGE pile of problems to climb out from under on a legal front.
He is an adult now, and needs to feel adult consequences if he won't act like one. He is fully able to get a job and support himself, even if he feels the job is 'beneath' him. If he chooses an illegal job, he needs to deal with those consequences with money he earns and not money you bail him out with. Until you stop bailing him out and tolerating his behavior, it won't change. You do NOT want to be supporting him in ten or twenty or thirty years, and if you don't make him accountable soon, it may get to that point. He has had 2 1/2 years to straighten out under your very generous and lenient rules. It is time for him to deal with the world's less lenient rules with-o you and husband as a buffer.
I am truly, deeply sorry it has come to this.
I do think that waiting until after Christmas is the best way to handle it though. I would make sure all gifts are very practical, like flannel shirts and socks. Maybe a couple of books, but nothing expensive, electronic or pawn-able.
Take time out of the holiday prep to pamper YOU. A massage, a new hairstyle, new outfit, book, whatever will recharge YOUR batteries, go and do it with a close friend. Leave your worries and your Mom at home for the day or however long it takes. Also let the kids deal wtih Gma for a night and go out iwth husband.