Have you ever experienced a conversation with someone who didn't see eye to eye with you? At some point it's bound to happen- whether with a spouse, sibling, loved one, relative, friend or colleague.
Before reacting, consider how much this person means to you. Be respectful even if they aren't.
Honestly, are you willing to damage a relationship because of a difference of opinion? Simply listen to their view. If you disagree, politely tell them so.