Things get better. As others have said in this thread Autism is viewed, at least in part, as a developmental disorder. My son, who is diagnosed with "High Functioning Autism" often strikes me has having the intellect of someone 1 or 2 years older than him and the emotional intelligence/behavior of someone 3 or 4 years younger than him. This leads to socially awkward moments when dealing with peers. He actually gets along quite well with younger kids. As he ages he keeps maturing, but he's just behind his peers.
My daughter is PDD-NOS which is just the big "other" category on the spectrum. She's a bit learning delayed. She's oppositional.
The key to success with both kids has been to find the right program/teachers. Teachers need to have autism training to know how to teach these kids. At one of the earlier schools we attended the principal actually suspended my son for a day for acting out. Later we were able to point the principal in the direction of some good autism training and now they know better how to deal with this situation.
It does get easier. You need to adapt. It's not your child's fault their autistic and it's not yours (beyond genetics anyway). You need to learn new parenting skills. You need to take respite when you can. Most importantly, you need to find a support network. Other parents of autistic kids are a great resource. There's a Dad's group in my area (there a lot more rare than the Mom's groups it seems).
Remember autism is a spectrum disorder. Starting with completely non-verbal nearly comatose people all the way up to people who might just be described as nerdy. Bill Gates, Isaac Newton, Einstein all had at least some of the signs of being on the spectrum. I think if you start looking at any highly successful person (Tiger Woods & Bill Clinton are springing to mind at the moment) you start to realize that they show some signs too. Non-autistics are called Neuro-Typicals (NT). I'e come to believe that NTs really are just that: typical. To be extraordinary, you are, by definition, not-typical. You have quirks. How many quirks and how large lead to your diagnosis along the spectrum. I think all men are created autistic. Some are just more autistic than others.