Hi Sue!
Please stop beating yourself up. If you can interact with, teach, maybe play out in the yard, and give your son love and attention, that's what counts. It's not taking him to the park or taking him to a movie. Don't focus on what you cannot give him in material matters, instead, reward yourself for being a kind, loving mom who can teach her son right from wrong and how to be a good person.
I have breif spells where I beat myself up for what I cannot give my son due to my panic attacks while driving. When those come on, I force myself to focus on the fact that I give him hugs and kisses and tell him I love him at every opportunity, that we spend lots of time reading and playing with trains, that we spend time working in the yard together, and that when I watch him, I see a thoughtful, considerate, polite, articulate, imaginative, make-his-own-fun little boy who, I pray, will continue to grow into a caring, loving, thoughtful man. (there's already enough ***hole, testosterone-laden jerks out there, my wife and I don't need to raise another one!)
Be kind to yourself. Reward yourself for what you can do and don't get down on yourself for what you cannot.
Find a good doctor you trust. Explore various treatment/therapy options with that person. You'll find something that does work - count on it!
Warmest~
