Book very informative but made me sad

I appreciate the book very much. It helped me a lot to know that other couples were struggling with the same type of issues. But it has also made me sad, and I have not finished reading it. The sadness is because it seems like my situation depends too much on what, if anything, my ADHD partner does to deal with the ADHD. I do not want my happiness to depend on someone else's actions which I cannot change.