How come I have skipped periods, but nobody else in the family has it?

Common. There is a lot of variation in bleeding between women. Sometimes women in a family may have a common reason for skipping periods (like pcos) but many times it is very individual. You should be evaluated, but there is usually no reason to worry. At least 30% of women at some point skip periods.
Seek evaluation. I agree with the previous answer. Just wanted to stress the point, "you should be evaluated." while true that skipping irregular cycles is not uncommon and usually benign, it is important that an etiology be sought. Pcos, thyroid disorders, pituitary tumor, hypothalamic amenorrhea, ovarian/adrenal tumors, perimenopause, are a few possible causes of irregular cycles, which may affect treatment.

Related Questions

How come I have skipped periods, but nobody else in the family has menstrual problems?

Missed Menses. Missed menses is not strictly a genetic disorder, so no one else need have symptom. We are finding genetic involved in more issues though. Common reasons for missed menses include pregnancy :), pco, hormone imbalance (thyroid, prolactin), weight changes (up or down), stress (usually physical), medications and unknown causes. We have good treatments. Talk with your doc.