Why not go to your parents' and ENJOY your day. You could send her a matter of fact text that the 'switch' can happen at your parents' house or she can tell you what time she'll be home and you'll meet her with Calla there and then.
I really think you should go spend the day with your folks. You need to recharge and refresh and get some space away from this. Greek
Totally agree, except for letting her decide when she's coming back. I think more along the lines of "you can come to my parents or this is when I'll be back home." Provided he chooses a reasonable time to be there, not midnight just for spitefulness or some such. Just seems to me like she's jerking him around so much that letting her make the decision of when gives her too much control still.