Several things helped me keep going: my family; running buddies; a great support group; and a cat.
This is the kitty that helped keep me from going crazy:
Amanda--AKA "Mana"--approx 9 years old
Image credit Gary
This cat is twitchy, meaning she'll just as soon nip at you as stand to be petted. She was a rescue kitty that we fostered ("fostered" meaning that you raise the cat awhile for the shelter, and when she doesn't get adopted she then is pretty much yours by default!). We bottle-fed Mana, but for all that loving contact we had with her as a tiny kitten, it still seems that the lack of a real cat mother left Mana a bit emotionally and behaviorally maladjusted.
I will say that as she gets older she is getting somewhat mellower and more loving.
Mana will leap up on my lap now a couple of times a night, until she gets too hot. Her cutest move is when she is in a sitting position and wants petted--she'll stand up on her haunches like a meerkat or prairie dog to reach my hand coming down for the head petting action.
The connection to Ultrarunning is tenuous, but real. Whenever I come back from a backcountry run, Mana checks me out thoroughly. I suppose the woodsy smells on my clothing and trail shoes are simply more fascinating than when I just do a "normal" road run.
Anyway, we truly hope to have Mana for awhile yet, but when her number is finally up, her epitaph will read, "A Good Kitty." And I'll remember and thank her for what she did for me.