Book Identification: 80s or 90s horror

I was wondering if you can help me remember this particular book I read when I was younger.

It was about a girl who played lacrosse. She lived in a New England setting, I believe. She often experienced supernatural things -- they happened in her neighborhood. When she'd get a bad feeling about an area or right before an event, the colors of her hair (silver, gold, and I think brown?) would separate. She had a younger sister who weaved a hair in her toothbrush, so she boiled her toothbrush to make it germ-free and instead melted it. She also befriended an elderly woman who would talk to her from time to time.

I think maybe there was a picture of a haunted house on the cover.

Thanks in advance for the help!