My goodness. 5 hours? No wonder you were exhausted. I don't think there is a given way to deal with the situation you were in. I know that this sounds a bit uncaring, but I'd say if you ever agree to meet with her again, (or anyone else where expectations could be unclear) make sure you have told them a set amount of time that you can be there. An hour or maybe two would have been quite enough to deal with. Try to surround yourself with people who make you smile today (even if you don't feel like smiling at the moment). Isolating could be a mistake, and it's probably tempting to do so after that meeting. Try to counteract ut by turning up the self care, and safeguarding against the HALT triggers.