Riding doesn't just belong to the skinny! *evil laughter* Ok, so most of the time it does. But, as a 'more to love' rider myself, I say let them! I can still ride better :-p. Ok, not really, but that's besides the point. Lol. (Sorry had caffeine today.) I'm actually pregnant, plus sized, and I ride 1-2 times a week.
Riding is a great way to loose weight, or maintain weight loss. It is also a great stress relief. Take it slowly getting back into it, find a good solid horse, and be free!