I've only recently discovered I suffer from something called 'Rejection Sensitive Dysphoria', related to having Asperger's (something else I only recently discovered about myself relatively late in life). I realise now that both the urge to write and the extreme pain of having your work rejected are central to this personal flaw.
I'm really in two minds whether I should continue trying to get anywhere with my books as the consequences of having my work rejected again and again are too personally damaging as for me it can trigger suicidal impulses. I've tried to protect myself against this by going through the CW MA route, trying my hardest and gaining distinctions all the way through, but then find out too late that this is no buffer against continued rejection.
It's alright to recommend 'keep on submitting' but bear in mind not everyone copes with rejection in the same way.