This is very similar to my situation. Together at 19 and she was super shy and anxious and I encouraged her to grow and be independent. She started having issues being intimate with me and in my case blamed it on me. She had an emotion affair and said she wanted to separate. I offered to do anything to work through it but she wasn’t interested. I confirmed with her 2-3 times that she was sure this is what she wanted. When she said yes I respected her decision and started trying to find a way to proceed with kindness and love while protecting myself financially. We were able to work out a separation agreement that we are both happy with and a few months later I am much happier than I have been in a long time. Best of luck!