Minnie, that must have been pretty tough. I had similarly poor results when my marriage fell apart in the six months before the Brighton marathon in 2010. I wasn't sleeping or eating properly and had no drive on my long runs especially. I was trying to use running as a distraction to what was happening in my personal life, but I think the long runs require you to be in a pretty good head space, and I found I had no energy and just couldn't push through any type of discomfort, and would find myself walking a lot. Consequently my training for the marathon was very poor, and although i made it round I promised that next time I'd give myself a fair crack of the whip.
Thankfully life has taken a turn for the better, and I'm enjoying my running now