Dear,
Right now, he is still young enough to be reached.. Later, when he is 18 - if he makes it that far, he will be prosecuted if caught doing these things like stealing things and cars. So, what do you see for him down the road.. and what do you see for yourself?
Would you rather he be upset with you for calling authorities for help now, or rage at you later for not caring enough for him (while he's stitting in jail)
He obviously has a problem that he needs help with, and so do you. If you cannot offer the 'total solution' alone, you should seek help from anyone with a plausible plan to help all of you.
It's certain that you cannot deal with this alone, and neither can your son, so you need to make a choice for the future of both of you.
Good luck dear, and don't feel alone. There are a lot more parents like you.. seek them out in a help group. That might help.
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