I can kind of understand how she feels. I had a good, stable childhood with loving parents. I don't know that I ever felt that it was my fault that I was sick, but more of, why am I sick or am I even really sick? I've also had trouble reaching out for help in groups. After I was in the hospital, I wanted to start group therapy, but I felt so out of place in the one group I could find, that I couldn't continue. In my mind, it felt like "Poor little white rich girl."

In a way, though, my issues were hereditary, but I didn't really see it. My mom had depression when she was my age. My dad's sister has several issues of her own that had her hospitalized at least once while they were growing up. Both of my grandmothers had issues with anxiety. But, like your cousin, I think these felt far away and unrelated to what was wrong with me (even though every single therapist asks you the first session...)

I think if you just keep reminding her that it is hereditary, that there is nothing to be ashamed of, and just overall being supportive, there really isn't much more you can do. If she isn't already, perhaps recommend she see a therapist (sometimes it helps to hear something from someone that's not related to you), or if you go to a group session, you could ask her if she'd like to come along.

If she's struggling with anxiety, the Anxiety and Phobia Workbook has a whole chapter on "causes" of anxiety, such as neuro-biological and family hereditary and such.

I think it's really great that you're being so supportive to your cousin. I wish my cousins had been more understanding of my issues, but c'est la vie.