I'd hardly consider that an "awesome" side effect. Weight loss from medicine isn't healthy - it's just removing fat. Your muscles aren't stronger, your body isn't in better shape, and your cholesterol will still be a problem. Eating nutritious food and exercising is the way to health. Losing weight is a natural consequence.

Personally I'd rather just have some fat removed then nothing at all. But maybe that's just me. Although as someone else has mentioned, take note of how much weight you're losing. A few pounds here and there is fine, but dramatic weight loss in a short time period is actually dangerous for the body. Just keep an eye on things, be thankful for the perk, and ignore your stepmom who obviously has her own issues. I'd also talk to your dad and tell her what she said if she treats you like this on a regular basis. Maybe even record her if he doesn't believe you. Because it's not ok for her to talk to you like that. I'm hoping this was a one time incident and she's not this evil all the time.

You're so edgy you could probably cut diamonds.