Lemur_Ninja said:
...she doesn't see a boyfriend as someone you like/love, she treats them more like a lap dog....
She apparently sees YOU as a lapdog too. In fact, she probably sees a great many other people as her personal servants.
You said you don't want to hurt your sister physically/mentally/emotionally, but she clearly does not grant you the same consideration. One-way predatory relationship are NOT healthy and you are allowing one to continue, even though you are the victim of the relationship. In fact, by allowing her to walk all over you, you are doing her less of a favor than if you snapped her back in line.
You may not want to admit it, but your sister is the typical stuck-up high-maintenance holier-than-thou ***** that most people want nothing to do with. If you don't stand up for yourself she
will take advantage of you like she has been.
A wise person once said "You haven't been a good parent if you've never been hated by your children." The same logic applies to older siblings and other mentors. You've coddled her too much and now she sees having people wait on her hand and foot as the status quo. Correct her before the rest of the world does, because I can guarantee you the world will be far harsher on her than you could ever be.