Missing him when he's not around

Does anyone else miss their SO when they just go to work or something? Like I feel so clingy because whenever he goes to work or I go to work or literally anytime we do anything away from each other I miss him so much. I just want to know it's normal. I feel like it's so unhealthy. I don't whine or anything about him leaving and I don't ask him to skip things but I just feel like i want him there. Tell me I'm not crazy....