Realizing that many of your fellow high school graduates (c/o 2004 in my case) are either: 1) Engaged
2) Getting married
3) Pregnant or already a parent
Then you realize that you only just started your 1st year of medicine and have another 3 years to go. Then another 3-4 more years of residency. And by the time you finish, will be in your late 20s or hitting 30.

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