Something I had to learn is that they're not trying to ask for help or treatment. It's one of those times where you're supposed to listen and commiserate, but not offer a fix. They likely already know that you're unable to help, and they likely already know that there isn't really a way to "fix" it, only ways to make it easier to deal with. And one of those ways is to talk with someone about it, which is probably why they brought it up. Ironically, you'll be helping so long as you don't offer help, just company.