I feel almost nothing....

I have been married for 13 years.  Frustration has always been a part of the marriage but I could deal with it.  The last 2 years though, I have finally reached my limit.  After a very up and down year my husband finally agreed to marriage counseling.  He has admitted that he is depressed and acknowledges that he shows all signs of being severely ADHD.  We have been to two sessions with a counselor that specializes in couples therapy as well as adult ADHD/ADD.  Hubby did complete the written evaluation the therapist asked him to do (after 7 days of me nagging him to do it) but has yet to agree to a full evaluation and has said that he will not, under any circumstances, go on medication.  But at least the counseling is a little progress.  The sessions have been lack luster at best with us only exploring basic communication methods, which I do realize is important.  But neither of us has opened up about anything really.  I will say that it seems that hubby is trying at times.  My problem?  When he does try, I am not impressed.  I almost feel like it is just too little to late.  He still isn't really taking much initiative but does do things if I ask him to (though not in any hurry).  He has even brought me flowers, given me some time to myself etc.  Again, I just say "Thanks".  I can't seem to muster up any real appreciation.  I feel terrible about this but I seem to be reacting to everything with skepticism.  This is really troublesome to me but I just don't know how to get myself back to a place that I can see him/us in a positive light.  Part of the issue is that the tension is still there.  We can be having a grand time and with one word or phrase one of us takes it the wrong way and *boom* silent tension and we retreat to separate rooms.  That is when I really start to think about all of my options and the serious possibility that the best thing would be for us to be apart for a while.  Wondering if a little distance might help us both.  I hate feeling like this.