Hi Zomese,
Okay--so deep breath, seriously, take one please. In slowly through your nose, out slowly from your mouth. Okay, now...what your MIL said, I agree, could be a major trigger. It already kept you up all night and now you're feeling anxious today. Do the Seroquel at night when agitated etc, Klonopin through the day when anxious. Verify this with your doc, but it's just like the doc said. Take the Seroquel at night if you're feeling that agitation or shift. You need to get your rest at least if you are in fact on the brink of an episode. Plus the Seroquel might help chase the symptoms away so you can control the episode. I think taking Seroquel through the day may sedate you a bit too much, so I would take the Klonopin instead, it has helped me calm down when I'm freaking out. But again, ask your doc.
Although I was just doing the exact same thing yesterday..he he..um try not to look too far ahead..like the whole week might be bad, depression etc. Just try to get through these moments, use your meds, try to vent to someone about the stressor, journal, go for a walk with someone so your head isn't busy thinking like crazy.
Just try to slow down a bit, and although your vacation is done, you can still be feeling well. Positive thinking and major coping, k? 
I'll keep my eye out for you.