Oh I know that feeling. My last cat, Mayo, I took him when he was two weeks older cause his mom, a stray cat, dumped him. He was very ill, he had a bad infection to an eye (he had a surgery at 6 months to remove the eye). I managed to save him and we can't leave him alone: me or my mom had to remain with him. One summer I wanted to bring my mom in Sicily to visit some friends and I bought an airplane ticket also for Mayo, cause it was impossible to think to leave him alone. Unfortunately he died at five years old: one night he was so freightened by thunders that he crossed the street without attention and a car hit him. Till then I have no heart to take another cat...