Writer's block is a symptom that is caused by a problem. Rather than trying to target the writer's block itself, target the cause.
OP isn't looking for advice on their depression, but I'll put it here for anyone who is interested anyway. Depression is something that can be overcome. It's hard, because it requires a lot of self discipline and, in the case of seasonal affective disorder, it's only something we can really work on when it shows up. Phototherapy can help, especially if you spend all day inside. Certain lights have been known to improve mood, like certain types of florescent lights. It might also help to have some sort of physical hobby, be it a work out routine or tinkering with your car. Cleaning the house works too, it doesn't have to be physically demanding.
If you insist on attacking the block itself... talk with your RP group/partner? I find it surprising how in a social hobby like this everyone insists on going at it alone as much as possible. Writer's block means everything you write looks like shit to you, so have someone else there to confirm it's not, or at the very least, help guide you to something that's not shit. People love giving their input on things and this is a resource you should be making use of.