Everyone has an opinion. The best you can hope for is that others respect yours. If they don’t, c’est la vie. Be a better person by accepting theirs. However, never hesitate to put yours out there.
Maybe you have an insight or an understanding. Although no one else agrees with it, by sharing it you may turn them on to a thought that may stimulate a thought, and there is no telling where it will take them. This is especially true if you try to stimulate thoughts that require them to look within themselves for a deeper understanding of Self. If that is achieved, then you have done a mighty thing.
Perhaps only one out of a thousand will hear you. In the Gospel According to Thomas, Jesus said, “I will choose you one out of a thousand, two in ten thousand.” If you have a thought and you believe it, then share it. If others reject you, so what? Brush it off and move on.
Never take rejection personally because there are two sides to that. On one level, you may be seeking out rejection for your own personal needs. If you find that this is a recurring situation in your life then it would be wise to seek out the reason behind it. It does fulfill a subconscious need.
On another level, they may need to vent and you just happen to be the trigger that shows up. You need to question both sides because, either way, you sought it out. But try not to take it personally.