I want to wake up and be in a differant life!

I began dating my now spouse in November 2010 and by November 2011 we were married. At that time she was everything I could ask for with potential for more!! Boy was I wrong!!!!!!! We just found out that she has ADD and now it has become a crutch. We started marriage counseling in April 2012 because being raised by a military family, I was not allowed to make excuses or give up easily and I had to FIND a way to make things happen...strong adapting skills if you will and I was determined to make this work. After marriage I felt like she lacked everything...She managed her symptoms before by smoking marijuana (says the therapist) so I had NO CLUE what I was getting myself into. I was the only one in her life that even cared enough to see that something was off...forgetting everything, spacing out when faced with harsh reality, suddenly not knowing how to do ANYTHING. I never know if it's her manipulating me (she grew up doing this daily to any and everyone to survive) or if its really the ADD. This has became extremely frustrating as I was a single mother prior to meeting her and I just found out my son has ADHD. I found myself being a mother to 2 children. I have always been supportive of her and encouraged her to reach for the stars....little did I know, she was just taking and not giving. We had many talks of how she needed to help out more and try to regain herself. She read a few pages on the net and started to realize a few things that she had been doing....THATS IT...bottom line is I do not want to be responsible for her and her nasty attitude. Everything I say to her hurts her feelings or makes her defensive and I frankly do not want to deal with that from someone who makes it CLEAR that they need me. I will NOT be taken advantage of! I have a child who depends on me and is learning his coping skills from me so I have a lot of say in how he manages his ADHD...For her...I would have to unravel 26 years of horrible coping skills and ghetto behavior as she was raised by the streets (not parents) and since I cant relate to that life and have no clue where to start I'd rather leave. I know this seems really harsh but I'm tired of understanding and saying its ok and lying to myself about this. This is NOT ok and I'm tired of understanding and I simply do not want to rewire my whole life to accommodate her so she can find out who she is all over again especially since she has such a sarcastic and truly NASTY attitude when I try to guide her or advise her of anything. She doesn't seem to understand or care how much responsibility this will be for me to pretty much raise her for the rest of my life...I have been drained and pumped with hope only to be drained again. My child comes first!!! I can not be any good to him if I waste all of my energy into her. She constantly mopes around feeling sorry for herself instead of trying to talk about our problems. She would rather isolate herself from everyone than to talk. I HATE IT! I'm tired of being embarrassed because of her bad people skills and her lack of confidence. WHERE IS THE PERSON I FREAKING MARRIED? I have gone back and forth with my emotions but always find myself extremely depressed and angry and I refuse to be that person. No one can tell the next person what they should do or how they should feel but venting feels really FREAKING awesome right now. I want to leave but I feel sorry for her cause she will run right back to the place that created the disfunctional mess she is today.  No one cares for her and she is really (or used to be) a sweet person but who can be attracted to their dependent? I never know if she really loves me since she never seen or felt love growing up.