A: First, you have to make sure the things your “friend” has been saying are out of line—or if you'’re simply being a tad neurotic and paranoid. (Please don'’t slap me for saying so, but that must be sorted first.) Consult a neutral third party for her opinion. If she says you’re overreacting, think about whether you’re being insecure and how to work on your relationship with your partner. (P.S. Paranoid is sooo not sexy.) But if she confirms that your flirty friend is out of line, drop that bestie. No real girlfriend would ever hit on the father of your children, unless she didn'’t respect you, your friendship, and herself. You deserve better. Period.