Best place in US for singles over 45 to live?

As a southern liberal, I'd like to live somewhere more diverse than the MS Delta.

In a little over a year, I'll be free to move anywhere in the US, so I'm planning my escape. I'm looking at areas that have lots of outdoor activities, hiking, camping, biking..etc, culture such as live music, museums, plays (little theater is a plus) and engaging communities/neighborhoods for people in my age bracket.

I've lived in New Orleans, which I loved, but the rental market is overpriced. Being frugal and working on retirement savings is a top priority for me. Austin comes up as a great place for singles, but I'm thinking it's more 20-30 year olds. Building meaningful relationships, romantic and non-romantic, are also a top priority.

My google research has listed mostly cities that have a high cost of living, which I'm trying to avoid. I'd love to get some anecdotal feedback or tips on how to research areas with my preferences. I'm getting an AD in Health Information Technology that will enable me to, among other things, work from home as a medical coder. So the job market isn't much of a factor.