Is it normal to not keep up...

Currently I am in a state of depression. I do have hereditary depression. It just ha come up again and it's super strong. My husband does not understand and that's okay. The biggest thong that is bothering me is that I cannot keep up when having sex. And because I can't keep up I feel like crap. It just puts me down a lot more and I just can't get out of my crappy mindset... Is this normal??? What can I do to fix it??? I'm so lost.