I Feel Guilty

i found out last october that my cat kiki la la has cancer in both ear c&%^s. one vet told me to put her to sleep or that she needed total ear c&%^ ablation. the second vet said the same. the third vet agreed but said he would remove the main mass in her one ear to stop the ear infections but that she would of course still have cancer. the surgery for the TECA was about 2,000 dollars per ear. i can't afford that. i opted to go with surgery to remove the mass for 800. i feel terrible that i can't do that surgery for her. i love her dearly and i'm pretty certain she's the best cat in the world. the vet said there's no way to be certain how much time she has. i'm having a hard time dealing with this. she's the sweetest creature i wish there was something i could do. i'm worried that i won't know when it's time to let her go. any advice? i feel that when the time comes that i should be with her but i'm not sure i can watch her die, i'm also not sure if i can deal with the guilt if i let her go through that alone. any thoughts or suggestions would be appreciated. i'm at a loss. she's my baby. i'm trying to just enjoy the time i have left with her but it's hard.