Most likely, he's bored and is just playing with his phone. Phone, email or text that "we need to talk". If what you want is a long-term relationship, approach it with your goals in mind. Even if it was a casual relationship, even if it was only a month, that's just low. But you know what? If it didn't sound dirty in this context, I'd less-hesitantly say "different strokes for different folks" But thank you to everyone who gave such helpful insight on a difficult subject.
For pointers on how to do it gently, see Miko 's fabulous how-to-dump-gently answer.
10 Rules For Dating When You Want a Serious Relationship
But, unless you feel the person is dangerous, there's no reason not to tell her in person. There is no unwritten rule about this. It's interesting that almost everyone seems totally sure of what the best method is You said "I generally believe that there is an unspoken exclusivity sentiment by the both of us" which tells me that breaking up via email would probably feel cruel and disrespectful to her. If folks care to know, I've read what everyone had to say and I'm choosing the middle ground and plan on calling her which actually was my first instinct, but since this is a new situation and my friends were split, I thought I'd ask some helpful internet strangers for advice. First, he complimented me warmly on my discount Gap leggings.