In the same way that one has to accept the weather, so one has to accept how one feels about life sometimes.

“Today's a crap day,” is a perfectly realistic approach.

It's all about finding a kind of mental umbrella. “Hey-ho, it's raining inside: it isn’t my fault and there's nothing I can do about it, but sit it out. But the sun may well come out tomorrow and when it does, I shall take full advantage.”