Wow, that's a long time to have a furry friend - sorry for your loss.
They're totally a part of the family...I know.
I lost my cat a few months ago too - she was approximately 18, but had only adopted us about 8 years ago.
I knew right away I was going to want another kitty - but I didn't want another kitty right away.
This weekend, we got a TINY little kitten. Cute as anything, a little sick so he's getting babied.
Going to be TOTALLY different for a while, especially - cuz Angel was never a little kitten with us.
Anyway - I feel for you, and take your time, but yeah - if you bond like that with a pet, you shouldn't rule out bringing another one into your life when the time is right.
This is me and my Tigga. Sadly Tiger had a cancerous tumor and I had to have him put down a couple months ago. He had a great 19 years of life, but i still miss him. Ive never had any other pet. Dont think ill ever get another cat. I love them but he was with me since i was 6 and i think any cat will just make me compare them. He was perfect for me. A real jackass just like me. He protected my room when the cleaning ladies would try to get in. Even chased one up on top of the counter in the kitchen, she had to yell for me to come get him.