I would hesitate to use stark white tile with cream cabinets and a counter with a similarly cream undertone. Maybe if you switch to a cream glass it won't feel so dark but will still be in the right color zone...

What colour are your walls? They look to be a strong white. The white tiles look 'good' because they are a pretty good match with the paint. If your walls are white, you already have a "white" up against the cream colours. Maybe that's why the aunts are telling you it will be fine.

I think the white is too stark. Even if your walls are white, why match the walls?

Go with the white, we know it seems stark but you can add nice pops of color in your accessories: hand towels, bowls etc.