Grown up enough to have a pet?

I grew up having cats. I had Sammy first, who was born before me, and then died when I was at primary school aged 18. Next came Biskit and Muffin, both of whom are now about 17. 

If you follow me on twitter, I do profess my love for the pair of them often, I'm very aware they're frail old ladies now, Biskit in particular hobbles rather than walks, and moans for attention constantly. She is a grumpy old lady, but she's still having an awesome life, plodding on and purring lots.

I don't live with my cats, and haven't for over 10 years. They do know who I am when I visit though! Biskit is oddly obsessed with being near me when I return home. It gets annoying, but I do love it too!

For most of my twenties I never considered getting a pet, despite loving what they can bring to your life. I still feel like my two belong to me, and I see them enough to satisfy my pet urges! I haven't felt enough of a 'grown up' to have pets full time, the commitment has always felt too large for my unpredictable life!

I liked being able to go away with no thoughts or plans, being able to stay out late, and pretty much just worrying about myself!

However, now I'm approaching 30, I am starting to think about getting my own pet. Eeeek! How did you decide to get a pet? How did you decide if you were 'ready'?