Boyfriend with ADD

Greetings, I have been dating a 45 year old, never married (was engaged) man that is a really great guy. We were together about 2 months. We have known each other for 8 or so months before dating. We live about an hour away from each other. I suspected he had ADD and was going to talk to him about it but our communitcations abruptly became almost completely stopped. He has some medication at my house and I found that he take Staterra which I understand is for ADD. We had been talking several times a day, together from Fri nite to Mon morn having one minor misunderstanding (I know it was because I was not clear in my communication) which we quickly resolved. He then got really busy with work (he is a landscaper- self employed) and when I asked if we were going to get together he said he had too much work and I distract him too much. He has had some financial trouble and is focusing on getting back on his feet. I know he has been busy with work, he says he will call but then does not. He has had some equipment trouble and large jobs with deadlines. Also included in the financial stress is IRS leins as a result of his ex fiance taking money and not doing her job. I know men have a hard time multitasking & they want to be the provider. I have also read that ADD can cause a lot of self esteem issues and so on. I have not talked to him for almost two weeks. Every 5 or so days he calls and leaves a long message on my voice mail explaining his current job and being busy, thanking me for my support and love and talk to you soon. No indication that there are troubles brewing. I am at a loss- I have not had the oppurtunity to talk to him and find out what is going on. I think he may assume I am going to "jump down his throat" which I am not- only want to know where we stand and why the sudden, abrupt change. He drinks a few beers everyday and I believe it is his respite along with the XBOX. My questions are: Is this behavior typical of a very busy, stressed man with ADD? How do I let him know that I know he has ADD and I want to help him, not change him and support him? What approach should I use to reach out and try to get our relationship back to where it was- assuming he is not wanting to break up which I really do not think is the case. if and when we get the relationship back how do I let him know that this has been very painful for me and not something I can or will be able to tolerate in the future. I know that men need to go to their caves but for weeks at a time? Thanks