Katie,
I can feel your pain, as I recall when I first learned that my kitty Sasha had feline diabetes. That was in the summer of 2006. Sasha has lived quite a long time with his diabetes under good control, until having some health issues in recent months as a 15 1/2 year old. I agree wholeheartedly with Gayle. First, it's important to find out what the diagnosis is, through your kitty's blood and urine tests.
Secondly, there is much that one can do at home without horrible veterinary expenses. All kinds of supportive and knowledgeable groups of people online, including this amazing one, help pet owners do this every day.
It's important to remember that many people do not understand treating a cat like a human member of the family, and thus giving that family member medical care and lots of love when such challenges arise. It says a lot that is great about you that you care enough to do this.
Contrary to any "burden" that people perceive with a diabetic cat or another issue, I found that it only deepened the deep, intimate bond that I have had with Sasha (and similarly with his brother Orlando, who passed away at age 16 1/2 in January). Take a deep breath, give yourself some time and space to learn what is ailing your kitty, and feel good about the way that you are standing up for your pet's care. You will get lots and lots of support in this.
Sending you and your kitty healing thoughts,
Susan and Sasha