Do you have to accept everyone as they are?

Do you have to accept everyone as they are ? I have recently been asking myself this for a few people in my life. Sure,  you can accept them and ignore them and continue on knowing how this person is, which is what I have done my whole life, but not without sadness, pain, disappointment.  I have done this way to long and have just come to the conclusion that I simply need to understand why this happens instead of letting it get me worked up. As I have always told my girls when someone has been mean to them or someone has said something downgrading to them, people do this because they don't like who they are or they portray to be something that they truly are the complete opposite of.  Why does one do this? They do it because it is the only way to have the self esteem they need, it makes them feel powerful because this is the only way to actually see the power by actually hurting someone and having the satisfaction that they brought someone down.  Well the truth to this is, those people are actually the weakest link on the human chain.
I am almost 40 and should not be letting myself get in disarray over this, so I'm not going to.  I have way to many good people in my life to let this effect me in anyway anymore.  So, I guess my answer to this is NO, you don't have to accept people as they are, that doesn't mean that you have to rid of them, but Never let any person cause you pain and if they are, then you need to let them know this and then continue on.  Again, another lesson I have always taught the girls as well is "kill them with kindness", this works so well and of course I preach it and don't follow it. Well I will from here on out.  All these solutions are so easy if you just take the time to think it through, understand why people do things if you can and just be the better person.  The resolution within yourself is success, A person that can deliberately hurt others over and over are far from successful.  Success is not material as most people seem to think. success is being happy, making the absolute best of what you have , learning from your mistakes and carrying those lessons on to others. Having an ego bigger than Texas and a black heart = unsuccess.  So the helpful resource for this reading is: Always think before you speak and take time to pay attention to your attitude towards others and just maybe you will catch something that needs a drastic change.