What determines when my period will return while breastfeeding? Baby is 8 mo. Still no period, but recently started having menstrual-like cramps/bloat

Feeding frequency. Several things seem to affect when your period comes back. Moms who breastfeed more frequently and who are thinner generally get their periods back later than moms who are heavier. It's important to use birth control after the first 6 months, because you can get pregnant before your period comes back.
Breastfeeding/menses. Hello, first- congratulations on the birth of your child. The lack of a cycle during breastfeeding (lactational amenorrhea) is very normal/expected. It is the result of breastfeeding on the ability of your ovaries to ovulate. It is not unusual for lack of cycles to be as long as 1-2 years, assuming you are breastfeeding solely. Remember, don't use breastfeeding as birth control!