Does a person's general health effect how bad their meth crash is?

Recently I've moved into my grandpa's house and have ended up living in the room across from my aunt and her husband who use meth pretty much as often as they can afford it.

My aunt is nearly 50, 4'10" and is morbidly obese. She does NO physical activity at all, we have a set of stairs in our house and she can barely make it up them. She eats horribly, doesn't leave the house except to make meth runs or ice cream runs,etc. Basically she treats herself like shit and it's a miracle she's alive WITHOUT the meth use.

On the other hand her husband, who is roughly the same age, is in a healthy weight range and goes and does construction work ... every now and then. Whenever he's got work. He still doesn't eat very good but he gets out and moves around more so he's in much better condition.

Even though they both use meth my aunt's crashes tend to be WAY worse than his. They started crashing last Saturday and my aunt's husband was basically fine and off to work by Monday whereas my aunt is still lying in bed moaning and being completely paranoid so I was wondering if this was because her health is so much worse? Also I don't know if this has an effect on it but my aunt has been using meth since she was roughly 20, I don't know how long her husband has been using. Also her crashes seem to be getting worse lately, as does her overall health.

TL;DR: My aunt has a way worse crash than her husband when they run out of meth. Is this because she's so much more unhealthy than him?