I wonder what type of seroquel you are taking? There are several kinds; one of which is an extended release tablet. These are what I take and I am stable throughout the day. There is another type that may be helpful in your situation. These are (small pink, 25mg) immediate release pills that are often prescribed as prn's (take as needed).

I also need to ask if depression is an issue and the reason you have specifically been prescribed seroquel instead of or along with a mood stabilizer.