Story: Dialogue

One of the exercises in the last writing group involved creating voices and characters out of objects and incorporating them into a dialogue. Dialogue is one of my weakest points. Here's what came out of the exercise:

-Is she asleep?
-I think so; after 3 days of insomnia, she's succumbed.
-Ah well, it was fun while it lasted. That was some car we crushed, wasn't it?
-Some car you crashed. She had no part in it. You had me locked in some backwater part of the brain, near the cerebellum.
-Sorry about that; you know you wouldn't have allowed her to frolic like that. She had more fun in the last few days than she's had in your entire dominion.
-And now she's going to have the biggest hangover.
-Yeah, well, you're going about it all wrong. You're treating it with lithium when ritalin would do the trick.
-You'd fry her brain. I should shove some lithium down your throat.
-Why not? Let's break into a pharmacy tomorrow, it'll be fun.
-We are not shoplifting. I've finally turned her around.
-But if you give me a chance, a whisper, she'll listen to me.
-How do you manage that, to poke your head in every few months?
-I build my house in the heart. I palpitate, I throb, I skip beats, I swoon her.
-You swoon her?
-It's a verb, trust me. I pressure her speech. I goad and plead. I masquerade as you for a bit. It's fun, you know, she believes me. She likes me much better than your cold-fisted government.
-You're talking rubbish. How could you usurp my throne? I sit upon the Turkish saddle, keep reins on the neurons tentacling. She calls herself by me. I wade through her mind and she sleeps and wakes in comfort that I linger. I cling. I define her.
-You define one side of her, the side that bores and languishes. The other side, the true self, starts a small revolt in your cerebral empire. She forgets her meds. I take over.
-Until I can put her back to sleep again.