Wounded Monarch butterfly - what do I do with her?

UPDATE: July 28th

Maggie passed over last night, safely ensconced in the Goldfish plant in the kitchen. The rain and winds were terrible, with thunder and lightning. She was blown off a plant outdoors, flung, sodden, to the ground. She'd taken some water.

Maggie's story

I'm so sad. I was out taking photographs of a new bird, Common Yellowthroat, by the mailbox. I saw this butterfly fly into the path of a car. She ended up on the road.
At first I popped her on the petunias in the planter. I tried giving her some of the hummingbird food, but she wasn't interested. Then, thought she might like the Milkweed, but she's likely in no mood to lay eggs. (My first Monarch caterpillar has disappeared, in its place was a spider. I'm not optimistic.)
I put her in the back yard overnight, on the Hops bine, as the wind was picking up and she cannot fly. This morning, she was drinking water from the rainfall on the plant leaves this morning. Her wings are soaking wet.

Now what?