Very good points, Nomesque. I have "How to Outwit Writer's Block" by Jenna Glatzer, and she points out that there are a number of legitimate reasons why you might be having trouble writing, including the fact that real life is just too complicated or stressful for you to be able to feel creative.
Do you belong to a writing group or website? I find them tremendously supportive - writing is a terribly lonely activity, and just having other people to grumble to about how things aren't going quite the way you planned can be hugely helpful.
Also, check out all the resources here:
http://hollylisle.com/ - some are free, none are expensive. Holly is a great teacher, I've done both her online courses and found them absolutely invaluable. Thanks to "How To Think Sideways" I wrote my first short story in a decade - and sold it! Now I'm putting a manuscript through her "How to Revise Your Novel" course and hope to have it ready to submit in a few months.
Good luck getting your mojo back!