What do you do when you lose your sense of humor? Life is terrible without it?

[a really big dude]

Where the hell do I go from here??? So I have had a really hard life in a lot of ways, not goin into detail it would take a book. I learned at an early age that a sense of humor was the only thing that was going to get me through this life.. So many years spent developing it through terrible times. Not even a year ago I could say the cleverest and funny things just off the top of my head. Theres been a LOT goin on in my life the past few months. I lost my job, the girl I thought I loved and the most of my friends are gone... thats all I'm gonna say it would take too much. For the last few months I have barely ever laughed where I used to laugh at everything. I was at my friends house last week and he just said outta nowhere " dude, you have become so freakin lame". Nothing is funny to me anymore. I don't have even a small shard of creativity left in my bones anymore. The only thing that has kept me going through all these years is humor. Well its gone now and I feel like I would rather just go ahead and die than feel as serious and depressed about everything like I do now. Is it even possible to get it back??
Not to mention that my sense of humor was the only thing I had going for me.