Have you considered a used bike?

Plenty of good deals to be found and often just as good, if not better, than many mid-range new bikes. Since you are just getting back into it, you'll find that over time you slowly get to know your riding style. Some people love drops, others hate. Some swear by internal gear hubs, others swear at them.

You'll probably find that certain things need tweaked or changed on any bike you ride as you find what works for you. Do you want to learn basic maintenance skills? I think some would argue that it's far easier and less intimidating to take a wrench and spend a few hours on a used bike than the nice, shiny new bike you just brought home.

How is crime in your area where the bike will get locked? Does your budget include rack, fenders, helmet (if so inclined), lights, locks, basic repair tools or any other commuting gear you might need?

Personally, I've been through 3 bikes so far. Found I prefer a more upright style with swept back bars, an internal gear hub and now a wider saddle. I'm in the process of getting my current bike set up as such.

Welcome and I hope you come to love bike commuting as much as the rest of us!