Sometimes, I regret. I even told my sister who lives

in China, I wished that I could turn back the time to 21 years ago. But if I didn't come to U.S. I probably would had regretted even more.
Several years ago, there was a show named "One way airline ticket" talked about these kind of feeling.

BTW, sorry for responding your post late, I couldn't read Chinese at work. So, my working condition is even worse than most of you :)