I agree with everyone here that you are a good bunny mommy and are doing your very best for Bud. He just wants to be loved and cared for in the home he's always known, and he is not judging you. He needs you more now in his older years, and knows your smell and sounds, so really he probably feels a lot better than you do right now. Bunnies can be very patient with us when we are stressed sometimes.
I have 3 simple suggestions for the sore hocks. 1. go with the soft throw rug suggestion already made. I can recommend what I've used - a 4'x5' cotton (I think) low pile area rug I got at Targets for about $20. It's a plain gray, and not hard to clean, or too dangerous to chew, or too expensive if it gets stained and you just want to toss it out later on. But it sits flat on any carpet or floor you are having trouble with. Sarita has found similar area rugs at Walmart.
2. You can put down a flannel 100% cotton flat twin bed sheet. It's just soft enough to be nice on feet, thin, washable, and covers a large area. I have mine over the cheap area rug and I tuck it under so it stays flat. The cotton makes it safe if nibbled. I use a pale green or blue, and found one for $5 at Walmart.
3. Bag Balm ointment for sore hocks. It comes in a square green tin and is kind of goofy sounding because it was invented for tender udders. Farmers use it to milk sore cows. But it was discovered to be really good for rabbit feet, dry skin and human feet as well. It's safe, but slightly medicated. I found my can at CVS drugstore with the hand lotions! I mean, I put it on my dry heels, wore socks over it to bed and it was noticeably better in the morning. Just a dab on Ben's feet so he doesn't lick off too much. Worth a try.
Use some on yourself, put on cute silly socks and lie down with a good novel. Breathe, drink sherry, light candles. You will feel better soon, too.