I'm so sorry, what an awful situation. Are you talking about ground squirrels or tree squirrels? We have only ground squirrels and they don't bother the roses very often. The rabbits will nibble, but mostly on young roses and I protect them by circling them with thorny rose branches. That might work even for tree squirrels. Any thorny branches can be used, for instance bougainvillea, or anything that will create a nasty physical barrier. I don't know enough about tree squirrels to know if this will really deter them. I feel so badly for you, that situation would turn me into a crazy person.

I've tried cayenne pepper spray, garlic spray, dried blood meal, two statuary owls which they use it to climb to the roses. I have tried something that makes an annoying noise every minute or so and nothing. The problem is aI live in an RV park (National Park) and we do have both tree squirrels, ground, chipmunks, and rabbits, etc. Rabbits don't get close to my containers but the chipmunks and the squirrels are other story. Can't wait until I move. They ate all the blooms of the Sharifa Asma yesterday. One survivor bloom of the Tamora also became dinner. The only one who has some is Jude but I am not holding any hopes. Ambridge's leaves are almost gone ; Falstar's blooms are cut in half as they ate the top part and I had to cut them. The only one that they seem to avoid- so far_ is Eglantyne . Jude had two of the bloom gone yesterday evening so I am guessing they are waiting for them to get a bit bigger. I wonder if they just show up during spring/summer . Really, I can't wait until I move . At least in a house you could fence or something. :(

Squirrels here also eat roses, but my dog has eaten enough of the squirrels that they stay in the backyard where there are no roses.

They're so cute, and I love to watch them in my BACK YARD, but they can be horribly destructive. Because of the squirrels, we have to keep our horse and cattle feed in galvanized trash cans. They're so smart they figured out how to open the cans, so we had to put bungee cords on the lids. I once had a squirrel running in and out of my garage several times a day for weeks on end. I finally realized he had eaten an entire bag of lawn fertilizer. I've often wondered how long he lived after that.

Your best bet would probably be a dog or cat with a taste for squirrel. It's quite a commitment but less work than spraying everything every time it rains.

If you live outside of the city limits, I would recommend a pellet gun and possibly a couple of live traps. You can thin them out and the newcomers will be more skiddish. It sounds a little cruel, but squirrels are cruel. I peacefully coexisted with them until I saw one stealing eggs from a Robin's nest. Since then, I have little mercy on them.

If you are in town, that's another matter and a cat would be your best bet.

Deer, squirrels, rabbits, raccoons even armadillos. I'm waiting for someone to post alligators. I gave up on sprays and use cages. Squirrels don't bother my roses, but one
( and only one) squirrel ate my drip watering system. I got rid of him by putting gopher bait where he was biting the drip watering. I don't like poison and have only used it one time over 28 years.

Most reliable safe and harmless deterrant for deer, rabbits, etc is The Scarecrow by Contech.
Seriously, it's the only thing that's reliably worked for me and i don't have to look at ugly chicken wire, spray liquid that washes off, etc.

They're $50 but worth the investment when you consider the amount of money you put into your yard. I got mine from Do My own Pest Control. It arrived in 8-9 days. (you don't have to apply the silly beak and eye stickers. Mine's all black and can hardly see it)
There are lots of videos on YouTube about it. For the smaller critters it's helpful to point it slightly downward.

I am so sorry to hear about your roses. I have tree squirrels in my backyard and they are real pest. They dig up all of my plants in pots including several herbs that I was trying to grow. They also stand on the pot and eat the hibiscus leaves. They haven't eaten any of my roses as yet. But this morning I had a bud on Evelyn and later when I came out, I noticed that it was gone. Not sure if it was the squirrel. I have two dogs which I just let loose in the yard whenever I spot them. Lately, I haven't seen them around much. Hope you can find a solution.