That's what I thought, because that's what I'd been told. And it made sense, because we were God's one true church. Leaving was tantamount to turning your back on God Himself and the only explanation for why anyone do that was that they had allowed Satan to deceive them. And then Satan would torment them for the rest of their lives. They would be angry, bitter and hateful and never find true peace. Those stray sheep might experience some momentary pleasures, but they weren't truly happy. Only we were.
So here I am. It's been over four years since I've attended a Mormon church service and a little over a year since I officially resigned my membership. I am more peaceful and content now than I ever was as a faithful Mormon. If rejecting the impossible and following your heart is the influence of Satan, please, sir, I'd like some more!
I once thought that leaving the Church was extremely rare, because supposedly apostates were miserable, and who would choose to be miserable? The truth is, thousands of us have left. If you're having doubts, you are not alone and using your brain is not the influence of Satan.
You can get out. You can have a normal life. Depending on your situation, you may have to deal with pressure and disappointment from family and friends, but nothing spiritually bad is going to happen to you.