I have only 15 dives and I want to dive more but in kentucky the water is pretty cold after first October to mid may or so. So I go ahead and invest in a drysuit?
If you have made the decision that diving is something you want to do in the long-term, or just have more money than you know what to do with, buy a dry suit. As it's a big investment, most of us need to have a good understanding of what water temperatures we will be diving in most of the time and compare this with our budget.
Some people are more susceptible to cold than others. If the water temp is in the mid 50's and the dive isn't expected to be prolonged, I don't want to dive dry. I like the water and being immersed in the environment. So this is something that's worth considering. Wet can be more fun, as long as your not cold.
Good luck with your choice!