What two excuses did Albert’s mother suggest as the cause of her husband’s alcoholism?

From the text:

‘He did it all for you, you know. When Lord Denton offered to sell him the farm ten years ago he took out the mortgage so that you’d have a farm of your own when you grow up. And it’s the mortgage that worries him sick and makes him drink. So if he isn’t himself from time to time you’ve no call to keep on about him. He’s not as well as he used to be and be can’t put in the work on the farm like he used. He’s over fifty, you know – children don’t think of their fathers as being old or young. And it’s the war too. The war worries him Albert. He’s worried prices will be falling back, and I think in his heart of hearts he feels he should be soldiering in France – but he’s too old for that. You’ve got to try to understand him, Albert. He deserves that much.’