How long has she been off feed? If she's been off feed for several months, I think a vet check for parasites or health issues is in order, before considering breeding her.
If she went off feed at the same time as some of your other snakes, then it's probably seasonal, and breeding her would be fine.
Monitor her weight--it's not how much she weighs now that counts, but how much she loses over the course of a month. Excessive weight loss means illness rather than just seasonal food-fussiness.