This is mastering in fooling people.
People hate themselves for a reason. It's called consciousness that is not asleep. This is a scream for help from your mind and soul that you have to change. And YOU CAN'T love yourself by imposing yourself that. It will make you just be less caring ab everything, even the important stuff and will increase your vanity.
Also bulls*it of course you should not give your all self to somebody else. You should not worship/love someone else more than God; don't be surprised if that person will not take care of your heart. It's normal to not do so, everyone has to take care of their own soul and destiny and have no responsability for other people's weakness or mistakes. And guess what that person is imperfect and hurts you. REALLY. There are mean people all over the world, so let's just love ourselves so that we can get rid of the mean people that are us.