Well, start learning what mormonism teaches. It will open your eyes.
Here are some great resources (all carefully sourced)
www.irr.org/mit
www.utlm.org
www.mormonoutreach.org
Listen to what the other exmos on here say, we were once lost but now have been found.
Heck, just listen to what the Mormons say on these threads. You’ll alternate between being outraged and confused.