Sounds like you are adjusting pretty well. Her getting into a close relationship may have helped you to let go.

I would caution you about something. She and this new guy will have their ups and downs, like any other couple. If you stay involved with her, you may get hopeful when she and him have spats, if she tells you all about it. They may even break up. You'ld be wise to not take too keen an interest in how this relationship of hers goes.