How is it that some find the sweetest most compassionate loving people while others find only those who have no heart at all?

There's too many reasons to ponder, you'll drive yourself crazy.
Just focus on yourself, take care of yourself, become a better person everyday (for yourself)
And stop yearning for another person because some how the universe will not give it to you until your secure and happy alone... Its like a test. That and desperation is a repellant even if you don't act desperate... The world and people senses it. You have to align yourself with what you want, if your aligned with loneliness, you will stay alone

Some people are subconsciously attracted to the same person over and over. There is something familiar they are not aware of.

I wish I knew the answer.

They're perhaps more patient and careful but have some luck too
No
Yes
Yes
Yes, some people choose to be

welll I really can't say....it will hurt anyone's feelings