I have a video with 7 likes and 21 dislikes, the reason is because it was a response video to about 4 or 5 different guys when a group of youtubers I started came to an end. Long story short, they wanted to control the purpose of my group and I wasn't having it, so they had a fit and decided to collectively leave and start something new without me. They all made videos saying why they left, in turn getting likes on all their videos. (btw, I did not respond to or even comment on their videos) So when I made my own video to tell my story, they had all their fans flood my video and dislike it simply because they agree with the uploaders they're subscribed to. Hell, it was like 4 or 5 on 1 and I didn't even throw any punches.
Anyway, I was quite happy after it was all over, I got to see the jealousy got to them, I basically did nothing but continued working on my channel. After dropping the extra weight I realized I was much better off on my own than trying to collectively cross-promote these people who don't even appreciate what I did for them. The evidence is my views and subscribers shooting up in the time I have not been worried about these foolish people.
So basically. Dislikes. Don't even let them get to you AT ALL. They don't matter. It's just a button that functions as a way for people to spread hate. Just do your damn hard work and work for the likes.