What an adorable pic!
I have this happen three times a year. During the cooler months that pass for winter around here, I am really into my greys and navy blues and blacks and other dark colors. Once it starts heating up, I get in the mood for brighter colors; until it gets stupid hot, at which point I gravitate towards colors that don't show dirt and sweat so badly.
I have learned the hard way: do NOT get rid of the bright colors when I'm not feeling them any more because I WILL want them again next year.
Sorry i don't have any real answers, but i totally understand the feeling.