How can people close there heart to the pain and suffering of this world?

We are all not perfect and we are all in a different place in our walk. Some Christians are hurting too much to even be able to reach out and help someone else, I was there at one time.I was homeless, sick, no where to go and my own family would not reach out to help, but another Christian did and allowed me some time to get back on my feet. Now I can reach out and help others and I like to do it because I have been through alot of hardship. Not all are selfish, there are alot that care and really try to hellp others. We do have hearts!