[@KoL]
First point is due to how she's aware that she won't be a magical girl forever, either through corruption, death, or family obligations. Also, there probably isn't any case that she's aware of where a 20-30 year old woman with a family became a magical girl, so yeeee.

Second point is because her brother is talented enough to live as he wants do, doing crazy shit that sounds like it belongs to a different genre, and she has no small amount of jealousy towards him in that regard.