I think it's time to let our old cat go, DH disagrees

[Gelasring]

I'm just wondering what others thoughts are. Our 15 yo cat has been declining for the last year. She has osteoarthritis but hasn't responded to any treatment we've tried. She's also got high blood pressure and a heart murmur. She's lost a lot of weight. The vet tried her on hyperthyroid meds but it made her worse if anything.
She's now at the stage where her back legs are very weak. She can walk but not very well. She can pull herself up on to a chair but falls getting back down.
She's not eating as well as she used to.
She still purrs when you stroke her but she's unable to come to us now.
She is still using the litter tray.
I think we need to let her go. I think her quality of life is poor and she's not going to get better.
DH thinks we should consider letting her go when she's actually unable to walk and/or use the litter tray. I don't think it's fair to let her get to that point.
What does everyone think?

It’s really hard, but I think you’re probably right. I think a lot of people leave it too long. Take care x

The advice you will hear from many people is better a day too early than a day too late. Animals hide their pain and discomfort, what you are seeing is only a fraction of what your cat is actually feeling. I have had 4 cats PTS over the years and its not easy at all. What does your vet say

Last time I saw the vet he said he didn't see a cat that was in pain and needed to be put down - that was around a month ago and I would agree at that point she was ok. DH took her on Monday and saw a different vet who seemed to think it was worth trying blood pressure meds and to review it in 2 weeks.
I don't know if I'm being selfish really not wanting to give it that long, I can't bear seeing her like this. I don't think DH can bear letting her go.