You can't regret a whole period in your life. . . . It's part of who you are, one of your stories.
It's not that the grass is greener on the other side, it's that you can never be on both sides of the lawn at the same time.
London on your own actually seems more exotic than Egypt on a tour.
It isn't such a bad thing to always know that someone on the other side of the world cares about you.
You learned that it was easy frighteningly easy to get lost in someone else's life accommodating him and stop being yourself. You learned to be wary about falling in love. And you learned that someone who loved you could stop loving you for some dark reason and even though that was bruising you were more resilient than you knew. Eventually you would get over it more or less.