I'm trying to build your wall

I'm all about giving second chances. I see absolutely nothing wrong with that, and I'm very thankful for everyone that's given me mine.
What I'm thinking about is how many second chances you should give to one single person. I know that I can be very harsh to people that have wronged me and sometimes my own wall might be a little bit to high. I just don't want to get hurt, and it really pains me to see people I love taking their walls down time after time only to get more hurt then ever and get absolutely nothing for it. No love, no friendship, just pain.
It's even more hard for me not to get involved. I don't often get involved, but if anyone hurts my friends or family I need them to know that it will never happen again. Unfortunately this decision is not always mine. I'm probably the most overprotective person I know but however much I want to, I can never build someone else's wall.
So yes, second chances, third chances for all I care and always, always forgive. You don't want to carry it around in your own life and never really be able to let go, so always forgive. But at some point you just have to realise that some people will never stop hurting you. This point has been crossed long ago, so build up your wall and let go.