I am frequently accused of being 'too kind,' but after reflecting on why I'm kind, it might very well be because the behavior comes from being a people pleaser. I'm afraid that someone won't like me so I'm overly nice to make sure everyone does. This is also a form of manipulation, too, isn't it? I'm kind so you like me.
However, it doesn't always work. And truthfully, I've worked on myself enough to where my normal response isn't always "Let me help you in any way I can even if it hurts me." I've learned there are many people out there who take advantage of people like me and I've learned to stop offering help or kindness to people who don't truly deserve it.