Tired, frustrated, and ready to give up

I'm 26, married with two children ages 9 months and 4 years old. My husband and I have been married for 4 years. I have ADD, but have known for quite a while and have it fairly under control. My husband has recently become diagnosed with ADHD. He has gone to counseling a couple times and is suppose to go on medication in about a week or two. I am excited to see how it will work, but at the same time, I'm not sure our marriage will even last to see the benefits. We have been having a hard time, but I feel like recently, I am just ready to give up. I feel invisible. Even when he looks at me, hes not looking at me. He's preoccupied. I feel completely alone in this marriage like he is absent, even though he is here. Having ADD myself, I do understand, but I don't feel like he even understands the toll its taking on me. I'm trying to hold on, but I'm losing it. He says things that are completely inappropriate and does not understand why I get upset. I do love him and I think he loves me, so I want this to work. I just don't know how much longer I can take this. He doesn't even hear me when I talk a lot of the time. I don't know what to do. Please help.