I would just like to know if there is any plugin or setting that will allow users to like and share images in the Simple Image Gallery Pro... So when they open an image it allows them to share it on facebook, twitter and google+?

There is a lightbox engine that has social sharing buttons but they share the item that the gallery belongs to and not the actual image.

You need to share an article/item to FB and since these images do not have a article of their own the main article will be shared.