Call your case worker and ask about respite care.
I also am dealing with this with my 15yr old - adhd and PDD (or Aspergers).
I don't know what kind of services there are available for you, I'm in the UK and we have a completely different system. But what struck me was your son's age and that you need to start thinking about the kind of support and skills he will need to make the transition from teenager to late teenager to adulthood. I know that here we have a service called Plus Youth that is dedicated to disabled teenagers (with a range of disability, not just ASD) and is designed to give them social skills/structre/opportunities whilst at the same time giving carers/families a break. It is centred around activities that the young people plan themselves (eg film making workshops, cookery and art classes, trips to the city, swimming and football trips, outdoor activities).
If there isn't a programme like that I was wondering if you can somehow construct one and pay for it using your son's disability benefits? Find a personal assistant/befriender/mentor that will work with your son for a few hours each month - maybe a regular weekly slot, or every two weeks - on specific tasks and activities. Involve him in chosing those tasks and activities (eg it might be going to the cinema, or riding a bus into town to do some shopping, or a sports activity, or cooking skills) and it will probably help if they are focussed around his interests. The person doesn't need to be qualified (I have constructed programmes using social work students who want a bit of experience and pocket money) - you could try your local youth groups or volunteer groups or church for starters. We have a local community service volunteers group who run a kind of befriending scheme for young adults with learning disabilities, for example. It might kill several birds with one stone: start teaching your son some independence and life skills, as well as giving you and your family a bit of a break. As he gets older he might want to think about employing this kind of person himself to help him to social/life skills support (he might be eligible for cash-and-counselling support schemes, for example, I don't know if these run where you live but they've been used for young adults successfully in pilots in some HMOs in lieu of state-provided carers).
Just a thought
Kirsty, mum to Euan (11, Asperger's Syndrome) Rohan (7, NT) and Maeve (4, NT)
"My definition of housework is to sweep the room with a glance"
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