My mother keeps rushing into relationships?

She did it with my sisters dad, my dad, a man she married, and a man she had an online relationship with and moved across the country to marry. They all keep ending badly and after this last divorce, it only took her 3 months to find a new man and she wants us to move in with him. How should I confront her about rethinking this, because it never turns out good and rushing will only put stress on us?