The reason we were given names when we were born is so that our parents and those around us had something unique to identify us by. I look at a name sort of like a PIN for a debit card or web site access. The only difference between a PIN and a name is the fact that as time passes and more children are born, a name that was once an extremely unique that no one else had can become at least somewhat common quite quickly. Usually our parents and those around us continue to use our names throughout the duration of our lifetime, or theirs. Occasionally family members and even some people we consider close friends will use pet names such as "sweetheart", but not as often as they use your name.
Enter someone very special in your life who for all intents and purposes I'm going to refer to as my boyfriend. Yes, you know who you are, and I'm pretty sure that everyone else reading this does as well! 
For as long as I can remember, we've been referring to each other, acknowledging each other, or getting each others' attention with one form of a pet name or another. Typically, the only time we use each other's names is if we're really pissed off at the other one, and trying to make a point. That's why when either one of us uses the other one's name in a "normal" context, it feels very weird, awkward, and uncomfortable, especially for me I think.
In fact, it feels so weird, awkward, and uncomfortable for me that when he does it, I almost always immediately correct him, and it's usually with a bit of a snippy tone because it does feel so awkward to me. By now you're probably asking yourself why does this feel so awkward to her? She's told us in about six different ways in the last five minutes that it feels awkward and uncomfortable to her, but why exactly is that? Although I can't pinpoint the exact reason, I feel like I can come pretty close.
First off, it goes back to what I said near the top. Usually the only time we use the other one's name is if we're really pissed off at each other, and trying to make a point. Using a pet name is a privilege in some ways, or at least that's what it's become for the two of us. Secondly, when you've done the very intimate things that we have, I believe there comes a point where names are no longer needed unless you feel the need to make a point. Thirdly, in my opinion, pet names are a term of endearment that I take very, very, very, very seriously! It took me a very, very, very long time to give my heart to someone the way I've given it to him, and as he is very well aware, that is extremely, extremely important to me! Even though we don't have an "official" label, and I'm okay with that on every level, I feel as though with everything that we've been through over the last almost 5 years, using our names when we're together unless it's to make a very strong point is weird, awkward, uncomfortable, and most of all, completely unnecessary! I really truly feel in my heart of hearts that the last five years have earned us those terms of endearment! Lastly, it shows me that even if he isn't thinking about a "official" label at the moment, and quite honestly and frankly, neither am I, he's at least willing to refer to me, and we're willing to refer to each other like we refer to no one else, which is a very comforting sign for me that we have a love for each other like we have love for no one else!
You know, language and the use of language has always been one of my very few great passions and something that I put a lot of effort and energy into! Obviously, this is no exception, and it's also one case where you could say words really do matter! 