I've never really understood the reasoning behind people throwing these elaborate parties to help them "celebrate" being single on Valentine's Day or any other day. Why do you need that or someone to tell you that "you need to love yourself." You aren't broken. There is nothing wrong with you that needs some type of elaborate celebration to try to salve over what ails you.
Being single is not a disease that needs a cure. It is simply either the interim between dating someone new, or a choice you make, or the reality of not being coupled with someone indefinitely. You do not need to prove to anyone that you are still worthy of love or living or whatever these ads, and single power videos tell you.
I think people also seem to forget in general, that just because someone is in a relationship, it doesn't mean they are automatically happy in the same way, someone being single, doesn't mean, now that they are single, their lives are going to be amazing. Happiness and loving yourself is a state of mind. You either are or you aren't.
If you aren't happy either in a relationship or by plastering the walls with "I love me stickers," or throwing yourself some "singles are great party," these things are not going to fix how you feel about yourself and make everything right in the world. The same thing goes for those that hop into their next relationship thinking that it's going to fix everything that was broken with their last. Someone else can't do that for you, if you don't already recognize your part in all of that, and work on yourself and being someone who is truly ready to start something new.