<human>: Give me the gist of the text in a nutshell

Back story to this: I am an 18 year old male and my friend is female of the same age. I have nothing against her and I have always considered her a very good and personal friend. We used to hang out and talk a lot, she made it clear that we were just friends and I was fine with that. But recently I got myself a new phone and her number wasn't transferred over, nor have I really made an effort to get it from any of our mutual friends. Lately a lot of our conversations have just been "hey. What's up. Not much, you? How's life." and then it starts to feel weird and forced. But when we hang out there is a lot more humour and laughter, and our conversations are more fluent. I saw her at the local mall the other day and we started off with the above conversations about what's new and stuff and made a few jokes before she had to leave which felt great, and then I realized I forgot to get her number again because it didnt occur to me at the time. I think she's awesome, we share quite a few interests but it seems we are drifting apart or something similar. 

Sorry if this is a giant wall of text, I posted it from my iPod.
<bot>: interactions seem weird or forced, conversations are normally awkward and fast despite sharing the same interests. How do I rekindle or break off the friendship?