l myself felt like you. Today I realise I should have never been affected by one or two opinions even if they have the power to damage my profile.
Steemit is VERY FAR AWAY from being decentralised, and your issue proves it.

1-plagiarisim is bad and WE ALL DO IT, since the only difference between right and wrong is to make a note at the botton saying were you copied from. Just try to follow the "polite" rules whenever possible.

2-People who notice your post are getting more upvotes will do anything possible to stop you. They have the power and they will not allow to come and take it.

3- KEEP POSTING and do not answer back to the people who just give you bad comments: be nice to the people is nice to youl