I just got done writing you a long message about this but it didn't go through, so here is the condensed version.
1) It doesn't matter how old you are, some vets are just like that. It happened to me recently and I am 33 yrs old and older than the vet. I didn't like the staff talking about me and my kitty behind closed doors or that they dismissed my concerns, barely answered my questions and never returned my phone calls. So I researched and found a vet that is great! Took time with me, explained things, interacted with my kitty and not just me. I am so happy I changed vets! Your money spends anywhere, if you don't like your vet, if you think they are dismissing you and your concerns or that they don't respect you because of your age, fire them and find someone else!
2) 100% Pumpkin Puree (not pie filling which can make them sick) is very good for cats and dogs with tummy issues, whether it is constipation or diarrhea. Message me for tips on getting a picky eater to eat it.
3) Make sure your kitty is staying hydrated, message me on how you can replace lost nutrients, minerals, vitamins and essential electrolytes.
4) Watch your kitties bum, if it looks like something other than poo is coming out that is an Emergent trip to the vet or Emergency vet hospital. Message me if you are interested in how to take care of red, swollen or raw bums from the loose stools.
I understand exactly how you feel and I have been in your situation with the constant loose stools. I have some things I have done in the past to help and i am more than happy to tell them to you if you are interested. Please note, I am not a Veterinarian or Vet Tech, but I do have a medical degree and many things are similar. Plus, I have past experience working with a variety of animals and am happy to help with suggestions, reassurance or whatever you may need. Just let me know.
Remember, nobody knows your cat like you, if you know something is wrong but the people you are going to aren't listening, find someone who will. Trust me, there are people who will listen. Keep us updated on how little Cherry is doing.