Would you let your spouse spend time alone with an EX?

If your spouse has (or hypathecial has) a now platonic friend who they used to date or had some kind of ual relationship with. Would you be comfortable with them going to lunch or dinner alone? What if this friend also was very flirtatious with your spouse (grabbing their or asking to, saying "you know I love you", and talking/joking about ual things)?