While we all have a rational and moral obligation to think critically about the things we believe, that doesn’t mean we have an obligation to fulfill that duty through unpleasant and unproductive debates with specific people we’re uninterested in talking to.
In other words, “I owe it to myself to be a person of integrity and intellectual honesty” does not equal “I owe a response to everyone who criticizes my beliefs and practices.”
Some conversations are constructive. Some conversations are not constructive. You have the right to choose the former and avoid the latter no matter how much your conversational partner believes he or she is indispensable to your enlightenment.
We live in a world of such diversity and technological advancement that we have an unprecedented ability to connect with brilliant thinkers and converse with people who have different points of view.
Very few of us, if any at all, are dependent upon one particular person in order to meet our needs for proper learning and personal growth.
If you don’t think you’re learning and growing from your interactions with someone, exercise your right to engage someone else.
No one has a monopoly on helping you learn and grow.