I identify with you. I've struggled with low-self esteem all my life and I still do. I've always been jealous of people who've done better than me. In secondary, I would be jealous of classmates who were achieving so much and in college, I felt intimidated by how opinionated and intelligent my classmates were. Anyway, enough about me, I shouldn't be writing about myself and I should be focused on you. I don't think you should be afraid to express your opinions. You're a good person, there's nothing wrong with what you think. If people are offended by your views, then you're better off without them. I can't give you a cure to low self-esteem as I'm struggling with that at the moment. If I can achieve happiness in my life, I might be able to give you an answer, but at the moment, nah.