Sounds like this guy is more into you than you are into him. You say you're in love, but maybe you're feelings for him don't quite rise to that level. It just seems to me that, when two people are in love, talking twice a day is pretty standard.

Rather than tell him to call less often, maybe you could just find a way to make the phone chats real short and sweet. Like, act glad that he's checking in, but have something you've got to get back to.

You say he's insecure. Maybe you are overly secure and don't find any challenge in holding his attention. You might be taking this guy for granted because you are so sure he is very emotionally needy of you.