Easier to forgive

Why is it so much easier to forgive a stranger than to forgive someone we love? If a person we never met before lied to us then apologized, we are much quicker to forgive them rather than if it was a person we have known for a long time. I guess its because we dint know the stranger (obviously), so we don't know what they are like and if they lie or hurt people in any other way a lot. Its much harder to forgive people we love because they aren't supposed to hurt us. When you love someone, you do everything you can to protect that person and keep them safe from any kind of danger, especially if its danger coming from yourself. SO if someone you love does hurt you, you start to question if they truly did love you in the first place. When you question, you start to doubt, and when you doubt, you live in fear that you cant be with that person again because you always know in the back of your head how badly they really can hurt you. Its hard to forgive someone we love because we are scared that we cant love them anymore.