the beetus shots are not bad actually, you pick up the scruff of the back skin like a triangle and poke that tent with the needle. it's subcutaneous so little drama there. they don't feel it.
what you might feel is the price tag of biologicals in the USA-- you can't buy generic and prices rose a lot in the past (not sure of current). if you can cross over to canada & buy veterinarian insulin you're in luck though.
my old cat got diabetes twice and twice went on remission. not just diet but steroid treatments might precipitate a condition. switching my cat to a wet and/or raw homemade diet helped him come back. but since he had other afflictions, feeding him was a juggling act.
anyway no more house cats for us, not now anyway. too hardcore.