You pay for insurance for the very reasons you used it! Why would you feel guilty? Believe me, they don't raise premiums based on one person...
As a mental health professional, I suggest you talk to someone about your fears. It 's very normal to be afraid of getting back on the bike. There are lots of women here on TE that have had very bad crashes; they all took the time they needed to get back to riding in whatever way they needed to.
Riding is such a huge part of my life, I know that if I was hurt from a crash, I would focus my recovery on getting back on my bike. I have a very good friend who broke his hip 2 months before we were supposed to go on a bike trip. It was a freak accident, but although he has a bit of a limp, he is as fast as ever on his bike. He took his rehab very seriously and did over and above what he needed to. This was 2 years ago and he still is doing focused personal training and massage to work on his injury.
And, I concur about riding in groups. I have done less and less of it in the past 2 years, for the reasons everyone has stated.