Because I live with the depressions most of the time, being able to laugh is really valuable to me. I think some will know where I am coming from.
I have had times when I can find no pleasure in anything... so I am grateful, if there are times when I can really laugh.
Marian Keyes (the writer) lives with depression, Her books - Under the Duvet and Further under the Duvet may be a tonic.
There is also Making it up as I go along.
if you can get hold of these - library, charity shop e.t.c do give them a go.
They may help.
Also try Marians web site - just because she can be quite candid about her depressions and all.
Please take every opportunity...to Laugh...if you can.