We euthanized our deaf and blind and I'm having doubts about it being too early

Hello, I'm having a rough moment and wanted to share what happened. So, two weeks ago my mother suddenly said that the next day she book an appointment with the vet to euthanize our family cat that has been living only with her since 5 years, since all the kids left the family house. I reacted by saying wtf no, and I then went to check on the cat the next day because i suspected my mother was being over the top and/or selfish without willing to adapt to her old age.

Now, to put the state of our cat into perspective, I was visiting my mother and so the cat every months or so, she was 19 years old, she had quite the decline in the last two year, especially last year, she gradually lost eyesight and ability to hear. So she became completely deaf and blind. But the rest was globally fine, she would still be able to go to the litter, she was still eating, less than before, she was still drinking, although she was drinking much more than before. She was still moving, although more slowly and a bit rough and she did bump into things and when no one was there she meowed very loudly until you came and touched her. She did look more slender. But she didn't seem into any pain. So, what I decided to do was to maintain the vet appointment, but not to euthanize her, but to check with the vet his objective point of view on the cat. He did not see any major health problems apart being deaf and blind and all the rest i described about her. He didn't rule out euthanizing her either, but he didn't said she needed to be euthanized either. The decision was basically on us, although he did say that at some point I would have to let her go.

So coming back from the vet my mother was acting not fine towards the cat, she basically let me know that she wouldn't stand too long no more taking care of the cat. So I decided to take her into my apartment. I took her in for 10 days total, I built a little ramp so she could reach a bed i bought her onto the couch, and she could get onto and out of the couch. I tried making her life easier. She adapted quite well. But it is true that her life seemed meaningless during the time ive had her at my place. She would sleep 90% of the time and then sometimes wake up when i came back from work and she would feel the slamming of the door. Then she would meow loudly and she would ask for somethings, i didn't always know what she wanted and sometimes i felt like she wanted something that she could not get anymore, like just, observing or being alive and being part of her environment. That's true that these moments were not always easy to live. And yeah sometimes she would meow really loudly and i tried to re assure her. But yeah after 15min or so, after eating or drinking or going to the litter, most of the time she would go back to her bed or i had to bring her back to her bed and then she would rest or sleep there again. Sometimes we cuddled, but she wasn't as cuddly as before. It did not seem like a good life to live honestly.

So I decided to say to my family that maybe it was indeed time to put her down, and now it is very hard to go trough because I'm sometimes feeling guilty that maybe she was put to sleep too early since she did still had life in her and she would purr when taking pets at some moments, she would even try to punch me back a bit when i tried to annoy her even tho she could not hear or see me. At the final moments at the vet she wasn't like laid down without energy on the table, no she was standing with the tail high. We went to the countryside to give her a proper burial with my mother. It is not easy right now. I keep telling myself that i've decided to put her down before she would start to suffer, but at the same time I feel like maybe it was too early. It hurts because she kept her dignity and courage until her last moments, even when she lost her sight and audition, she kept going. But we/I ended her.