Lately, my LTR has been in a sad/depressive state because of problems out of her control. I won't go too much into her problem itself because it isn't relevant. What is relevant, is how it affects me. Now I'd like to say I'm not investing myself in her problems, but empathy is a bitch. I hate coming back home in the evening to a sad person and attempt to cheer her up. It's not really a situation I can give advice to her about because it's beyond her reach, and she knows this and doesn't whine much about it, which I respect. However I can't stand the general gloomy energy in the house and it brings me down. She has to wait a couple weeks to know if her problems will be resolved or not. Till then, how do I strike a balance between investing/ not giving a fuck in an LTR?