Medication waste?

My wife (F 33) is upset about my (mtf 36) medication and I'm trying to see if anyone has a way to explain it to her. The Esterdiol comes in 5ml vials and there is over half left over by the end of one. She isn't upset about me being on HRT, but doesn't like the waste because it is expensive. I know they don't make smaller vials and had to explain that, but it hasn't helped. Anyone else had this experience?