I've just got back from the vets - we had to have her put to sleep.
DS woke us up at 6.50 and I could hear her miaowing downstairs, but didn't think much of it because perhaps she was seeing off another cat, or just wanting her breakfast. God, I feel so guilty. In fact, as DH found out when he went down ten minutes later, she was wedged behind the washing machine (we haven't got round to putting plinths at the bottoms of the kitchen cupboards, so she must have wriggled under there) and wouldn't/couldn't come out. It took DH a while to locate her, and then a while to move things out. She couldn't put her weight on her front paw at all.
Anyway, got her to the vet as soon as possible and were told it was a stroke, and she was probably in pain and certainly pretty out of it. So it was quite an easy decision to make, which is such a relief. But she was only 13, which isn't so old for cats these days. She had an ongoing kidney problem - they were very slowly deteriorating and she was on medication for that - so in many ways it's a relief not to have to see her go downhill slowly over the next few years. But I really wasn't ready to lose her.
DS is only 2 and has a sort of love/hate thing with her, but is fond of her and of course, has no way of knowing what's happened. He saw her peacefully 'sleeping' on the floor in the vet's just now and keeps on saying 'Martha sleeping' and then asks if she's coming home. How on earth do I deal with that? He's too young to understand dead, and I don't want to scare him.
Oh, my poor cat. She was so beautiful. I think I've given her rather short shrift since DS came along, and I feel so guilty for all the times I've pushed her aside because she was irritating me, or getting in the way.