My wife was as reluctant as you are. After 23 years of no - she finally agreed to try. I wouldn't say she loves it - but she asks for anal play no and anal sex doesn't cause her any pain.
It takes time, and lots of lube - and a bit of determination on your part to find what works. Start with fingers, then small vibes, then a butt plug or two. By the time you can accommodate a 1.5" diameter butt plug, you are about ready to try anal sex.
I also suggest that do anal play with your husband - the pleasure/pain he experiences will help him understand what you are experiencing. What's good for the goose - is good for the gander. In fact it was a couple of years of anal play on me that convinced her to try it out for herself.
Read/watch what's available from Jaia or Tristan Taormino - they have good guides that you and your partner can use. They use to carry them on EF - but you may have to search for them on Amazon.