How do I tell my girlfriend that she is being a little immature without hurting her feelings?

I am in a long distance relationship with someone and things were going great. We had great conversations, have a lot in common, etc. We met for the first time and had a great time and spent about a week together. Ever since then, it has gotten a little too "possessive". She wants to talk about 5 times a day and texts about 40-50. We fell asleep on the phone one night and woke up on the line together, and now she wants to go to sleep on the phone with me every night. I've done it for the past two weeks and it is starting to mess up my sleep pattern. In the course of a 30 minute conversation, she will say "I love you" about 5-10 times. It's not that I don't like saying "I love you", I would say it everyday, but, its a meaningful statement and it just seems like she is wearing it out, and I don't understand why she feels the need to say it so much. The worst thing is that the sleeping on the phone thing has started a few arguements in which she will get pissed because the call will drop while I'm asleep and I will wake up in the morining literally to 6-8 missed calls and several voicemails, and she will be angry that I didn't answer when we talk that next day. I don't think we should be fighting over something like that. She also flipped out on me recently because she noticed my mobile phone number was available to my friends on Facebook and demanded that I take it off so no one could see it, which also started an arguement. This is all starting to piss me off and worse, turn me off. We are 30 years old and I feel that this behavior is very immature, but I don't want to chastise someone for loving me. How do I tell her that I think she needs to grow up a little without hurting her feelings?