Depressed

I've been feeling really down lately and alone. I'm not pregnant or on my period or anything. I just feel like no one cares or has time for me anymore. I'm also feeling really helpless because my grandpa is pretty much dying in the hospital and there's nothing I can do about it. I told my boyfriend how I was feeling and he felt bad and tried to cheer me up but I just can't shake this feeling. Any advice?