My mate was first to drop my bike. Being used to riding a Ducati spoortsbike (and being a bit of a shortarse), he was not ready for the weight of the Explorer when we came to a stop. He leaned against the slight gradient and it was enough to have him on the ground with the bike almost on top of him.
I came close to dropping it in exactly the same situation as you OP, not paying attention to the slope of the road when i came to a stop. Strained a few muscles keeping it from tipping over and very, very slowly eased it back to vertical but it was a close call.
I have since dropped it when moving it around by hand in my driveway after a few beers (silly idea, right!).
Learn from your mistake, it's as simple as that.