YA Supernatural/ Fantasy. Girl has an imaginary friend in the attic by a lake and she's dragged in after the ice on the lake thaws. Read around 2017.

[Ava]

it's been a long while. i think the cover had a tilted pov and there was a gothic looking house on it and a grave with a statue in the front. i cannot for the life of me remember what book it was and i've been trying to find it for years!

[Kris]

Ava, around what year did you read this book? (The book you mention was published three years ago.)

Is it written for adults for teens?

[Ava]

i read this about eight(ish) years ago, pretty sure it was made for young adults

[Rainbowheart]

Probably too old, Mirror of Danger?

The ghost girl tries to drown the MC in a frozen pond.