Desperately looking for an old horror movie?

This movie is about a soldier that comes him form the service but is quite strange. Turns out he is dead and needs to feed on human blood to survive. This mother knows it and in the end when the police are on to him she helps him escape back to the cemetary and into his grave. Circa 1969 or early 70ish. I think William Castle but not sure. Please help me find it! Thanks