ADD Partner feels I am Critial and Hurtful by trying to deal with our issues

Hello - I am new and here is my story:

I am living with a man that I am totally in love with - we have been together for over 2 years, and lived together for almost 1 year.  We both have great jobs and many hobbies.  He has suffered from ADD his whole life, but only in the last year or so has he been interested in looking for a 'solution'.  Our relationship has been full of hardships, fights, and disagreements on everything from sex to commitment, but only in the last few weeks have we both agreed that my partners ADD has been a catalyst for all of the issues we have had.   

Currently he has an appointment with a Doc which he would really like to begin taking medication.  Meanwhile - now that we both are aware of the problems that his ADD causes we are fighting very hard to stop the cycle of problems associated with it.  Ex. - I feel neglected, therefor I 'nag' or remind him that I need love and affection, this makes him upset which causes him to become angry or just totally silent and shut-down and REPEAT.  

I know that sometimes I say things in a very critical way - he has even said it feels like I am treating him like he is a child and I am reprimanding him, or 'bringing him down' or making him feel bad about the way he is.  I try my best not to communicate like this - but it is so difficult because there are some days that he responds well to simple, short sentences  like "when you do ______ I feel _____" or "it is really hard for us to _____ if we are dealing with ____".  But it seems like there is no GOOD way to communicate my feelings in a way that makes him understand - or if there is a way I feel like it is different every single day.

Does any one have experience with this?

We have both decided to fight hard for this to work, but if there is ZERO progress in 6 months, then we have both decided to split ways.  We have come very far considering the things we have delt with together, but at this point I am making him feel like he sucks and he is making me feel the same way - its just not fair to do since we love each other very much.

Thank you - any advice or guidance would be greatly appreciated.