Non Add spouse looking at the future

This past week or so, I realized my husband is probably ADD.  We have been married for 21 years and have four children, at least two of them might have ADD and one of those two has a learning disability. 

At first it was a relief to find out that all these years my husband's actions weren't because of character flaws or uncaring towards me.  Now that the relief has worn off, I am experiencing a terrible grief.   Let me explain.

Before I met my husband, I had been in co-dependency therapy for a year because of my relationship problems with an alcoholic.  I had kicked the alcoholic out of my life (literally made him leave) because I could not deal with the vision of years of me having to live a "separate"  life within the relationship and of years of being the thinking person, the "mother"  in the relationship. I also didn't want to face years of going to therapy or support groups; I didn't want all that to consume my life.    I didn't get a childhood so the idea of having to still be the lonly responsible one was too much to bear.  A year after I got the alcoholic out of my life, I met my current husband.  He was so sweet, so much nicer than the acloholic, so affectionate that I fell in love with him.  We lived together for a year and then got married.  I love him deeply but from the beginning, things were not quite right.  All the ADD stuff about not being on time, being distracted and having job problems were happening and my co-dependency kicked in and I began to do the bills, and "rescue"  us every time something went wrong. 

We did fertility treatments for five years and then had healthy twin girls.  All of a sudden, I felt overwhelmed because I was alone, having to be a mother  to them AND him and he was always running away to "go somewhere."  He fell into a deep depression right after the girls were born and ended up going on zoloft.  It seemed to help the depression and for the first time in over five years, he stopped being so restless and was able to deal with things better.  He stopped taking it after 2 years because he said they took away his creativity and made him too numb. 

To make this short, he is now 56, and the last few years have been hell with seven job losses and now he is trying to career change.  He seems to be getting worse about his forgetfulness and stuff.  I am feeling more and more like a parent and my resentment was getting between us. 

Now that I know he has ADD, the grief almost overwhelming  because this means I am facing the very thing I left the alcoholic for;  years of having to do all the thinking, of having to be the parent, of not having an equal partner, of being consumed by this and having to go to therapy and support groups for the rest of my life.  I just wanted a NORMAL life.    I didn't get to have a childhood, all I wanted was a marriage where I could rely on my spouse to take up some of the load and instead I have a fifth child.  I love him so much but this is hurting so badly.  I don't want another child, I want a partner.  This hurts so much, I don't even know where to start.  All the advice I read, even here, still puts the non-ADD spouse into the role of "keeper"  and "thinker"  and "responsible one"  and I don't know if I can keep being all that.  It isn't fair to me.  Why has this happened to me despite all the therapy and progress I was making on my co-dependency?  I really made serious changes until I married this man.  His ADD has bumped me right back into  the co-dependency "parent"  mode.  I am experiencing emotional pain that I have been stuffing for years.  I have been being everythign for everybody (classic co-dependent) and it has made me unhappy, unhealthy and in pain. 

I don't mind taking care of myself and the kids, but having to be the thinker and parent for my spouse was not what I married for.  What do I do with all this grief and pain?  How do I overcome it and get to a point where I don't feel so unhappy?  I don't want a divorce, I love this man and he isn't as ADD as some; he shows his love a lot and is still very affectionate.  He is as sweet and loving as ever.  Besides, we have four kids and as a child of divorce, I know what that is like and I will NOT divorce my husband over this because it would damage the kids irreparably and hurt him deeply.  Yet to be healthy, I have to find some way to make sure I am happy, too.  (Co-dependents are really good at making everyone else happy while not thinking of themselves;  I cannot do that or I will become even more unhealthy.)  Yet if that means getting a separate life within the marriage, then why be married at all except for the kids?  The grief also is because I have realized that he will never be the husband I need even though I love him.  So do I really love him or is it the co-dependency?  I don't know what to think. 

Any advice for me?