Maybe she doesn't realize all the changes to her body and health issues that can arise as a result of going into menopause. If she's only looking at it from a perspective of "can't have kids" then it's not surprising she's not hysterical, she doesn't want any, regardless of what she says.
Yeah, the real issue here is that she's so ignorant to the female body that she doesn't really feel need to care about her inevitable and immediate onset menopause.Menopause causes you to lose bone density and develop osteoporosis. Her skeleton is already taxed enough as it is trying to carry her weight; if it gets brittle and she stays this size, she's going to be in unbearable pain from all the tiny fractures, especially in her vertebrae.
I really should just remind myself that Amber is truly a moron before I post anything about her. At any rate, she's so fucked.