Welcome to the club! A child with special needs turns life upside down for quite a while. From the families we have known in 20 years of psychology practice there is really no other way to begin other than what you describe in terms of immersing yourself in your child's treatment.
This is the real world of autism in the beginning of the journey. While it can be painful to say good bye to the child of your dreams, you can say hello now to the child who needs you just as much if not more as you get to know his/her unique personality and development. As psychologists, we see parents fall in love with their child all over again in ways they could have never imagined. First, we try to help people look at their grief. It doesn't help to pretend to be positive when underneath you may be lonely, afraid, or sad. The longing for the healthy child or a typical existence may endure. You have to learn to live with that yearning.
Take some breaks for yourself. Therapy is important but it isn't everything. As you get involved in the autism community, your isolation can lessen. Granted it is not what you were expecting, but just like your child, it can be very rewarding and meaningful.
Advice from Dr. Cindy Ariel
The initial period of learning about autism and all of the necessary therapies and treatments can be isolating, indeed. We are also often sad at first, or angry that our life with a child who has special needs is different than the one we dreamed of and different than the lives of most of those we see around us. Our ideal real world is often different than the world we actually live in. Still, there are many ways to work towards making your life more of how you want it to be.
Depending upon the functioning level of your child there are many parent groups to join, special sports teams to coach, and class activities that you can be a part of. Sometime the issue reflects difficulty in accepting who your child is with his/her specific limitations and abilities. It may not feel normal or coincide with the dream you had for how your life would turn out.
As you begin to get more involved in the special needs community there will be less isolation and more activity and company of others. This involvement often helps to make parents feel more normal as it ironically provides more chances for typical activity and interaction with others. Over time, life and ideals change and you will begin to dream new dreams for your real world.