How do you keep going when you have nothing left to give? (Depression)

How do you continue to function when you’re experiencing particularly bad depression?
I’ve been here before, but it’s different now as I’m living over 4 hours drive away from any family members.
I do not have someone who will make sure/cares if I get out of bed from one day to the next. I am at that stage where getting out of bed is a huge struggle.
I cannot think, critically or otherwise.
I work from home normally and am struggling to hold that together.
I cannot keep up with my studies.

What do you do to stay afloat when breathing feels like an enormous effort?