Not every friend has to understand your goals. They just can’t make fun of them.

Understanding is optional and respect is not. Plenty of good friends will never quite get why you care about the thing you care about, and that is fine, because comprehension was never the requirement. Mockery is a different matter: it makes the goal more expensive to pursue in front of them, so you start hiding it, and the hiding costs you more than the laughing did.

Tell one friend what you are actually working on and watch the first reaction. If it is kind confusion, keep them close. If it is a joke at your expense twice, stop handing them the material.