I think there's a fine line to toe there though. If someone is negatively impacting your enjoyment of life, is it morally dubious to cut them out? If you live your life for other people you will be absolutely miserable. It's not that I'm "taking" from others to get what I want, it's that I'm living my life for me and no one else.
The point, really, is that being comfortable with yourself and your life without an external factor is important as well. I can guarantee you MANY more relationships have failed and exploded because of someone making their partner their only source of happiness than have failed because everyone knows what they want from the relationship.
Lasting loves requires hard work and sacrifice yes, but not at detriment to yourself. If you're changing your own negative habits that's one thing, but it's entirely another to live your life based on what others expect. There's a reason that "self-love stuff" gets drilled into your head: you can't have a healthy relationship if you're miserable with your life.
Or, put simply:
It's not easier said than done though. You recognize that you forced yourself to like her... don't do it again? Relationships hurt, life hurts, the sooner you learn to accept that some people are going to be hurt MORE by your attempts not to hurt them, the better off you'll be. For example, what would be worse? Shooting your shot and not having a chance, or being led on for months? Years?
Let me be absolutely clear that I am in no way advocating malicious selfishness. Taking advantage of others is a horrible thing to do; doing what you want without thought for others is a horrible thing to do. That being said, allowing yourself to be taken advantage of is also a horrible thing to do.
Don't put someone on a pedestal and put them above yourself. If for no other reason than you'll get stepped all over. Being mature, independent, capable, and confident is a billion times more attractive than not.