This friend and I have a complicated history. We dated off and on, then decided to remain friends. When we talk about positive things, we have a good relationship. We're comfortable with each other, know each other well, and have pleasant conversations. We also have similar hobbies.
They have fallen into a bit of bad luck with their finances and are estranged from their family. They continually complain about their finances and their family. When they start on these topics, I expect to spend the next hour or so saying reflective things like, "You must be terrified because of the chance of not making rent" or "I know it's hard to lose your family" until they wear themselves out and go home or hang up the phone. I get frustrated because they circle around the same topic over and over. They also seem unable or unwilling to listen to problem-solving. I also can't relate because I have a good relationship with my family and am secure financially. Finally, I strongly believe that it's important to never look back and to always look forward - whereas my friend seems to enjoy gnawing on old wounds.
They occasionally allude to suicide, and say things like, "I don't know how I can go on". They have a history of suicide attempts. I read articles about how to talk to suicidal people and apply that advice in our conversations. I've helped them to find a doctor, and have provided them with numbers to suicide hotlines. I don't feel comfortable with this responsibility. They were put on anti-depressants, but have been unable to afford their prescription and are no longer taking them.
I'm losing my patience, and my friend has noticed that I've begun to withdraw. I feel optimistic about my future and this friendship has become a burden. I'd like to maintain the good parts of our friendship, but I don't want to be their psychologist.
How do I stop them from dumping their negative emotions on me, without making them crack?