No more empathy for my pwbpd

Does anyone else feel completely drained and doesn't feel empathy anymore when their pwbpd talks about their trauma?

All the conversations I have with my boyfriend are about the fact that he feels alone, his low self-esteem, and his dark thoughts. All the conversations require so much empathy. I'm at a point where I don't even want to talk anymore, and he's really not okay. I feel like a bad person because I genuinely lost the sense of care I had for him. I got tired of being there for someone who isn't there for himself. I feel like talking to him drains all my happiness, and he wants me to be my optimistic self. He doesn't understand that pessimism is just as contagious as optimism and trying to hype him up for so long got so tiring I kind of feel depressed with him.

Am I the only one?