This relationship is not moving forward in the direction desired by her, but she is so thankful to have had his love, this love is so hard to let go of despite the need to move on. She has to let him go and move on with her life because it is what is best and it is so hard, she may have tried many times but couldn't just let go knowing he was such a wonderful man. In a sense, he held her back for his own selfish reasons too and then after so much heartache they both had to be set free. She will not forget what they shared, neither will he but it's time to move on, and let go for good. It's better to have loved and lost then to never have loved.