Just because you are seeing human-like shadow forms does not mean your house is haunted (although it could be), and it doesn't mean you are crazy. When beginning to investigate such activity, you need to find out if there is a physical cause. One common cause is the existence of relatively high levels of electromagnetic fields (EMF). EMF have been shown to cause illusions, hallucinations, and even feelings of uneasiness or dread. You should have a licensed electrician check your home for EMF levels.
If your home's EMF levels are normal, then you might consider contacting a paranormal research group in your area -- preferably one that takes a "scientific" approach to an investigation. They probably also will check for EMF levels and also see if the shadows might be caused by outside passing car lights or some other normal source. Only when all possible normal sources have been ruled out might you consider that there is haunting activity. Be wary of paranormal research groups that jump to this conclusion too quickly. Usually, other kinds of haunting activity will add evidence leading to such a conclusion.
If they do suspect that there is genuine haunting activity, there may be little they can do about it. Sometimes so-called "cleansing" rituals help, sometimes they don't. Unless the activity becomes unbearable for some reason, you might want to just live with it and ignore it. Most often, such activity fades away of its own accord. It's highly unlikely that it is harmful or "evil" in any way.