<human>: For the past several months I [24F] been seeing this guy [23M]. Things have been fairly casual between us, we go on dates and have sex but there is no defined commitment to each other. I really like him and have immensely enjoyed the time I've spent with him. Unfortunately he hasn't been communicating with me lately, and we haven't seen each other in a while. I suspect that this is because he might be wanting to end whatever it is we have going on and see other people. 

I'm okay with this, in fact I half expected that this would happen when we first started dating, as I knew that neither of us were looking for anything serious. But for some reason I've been feeling extremely upset, tense, and unsettled lately. There are a few other things going on in my life that could be contributing, but this definitely has a large part to do with it. 

Being with friends helps, but it doesn't really make the anxiety go away, especially since the majority of them are in their own committed relationships right now. Furthermore, none of them really understand why I'm upset because it wasn't a real relationship to begin with. 

I've had a few major breakups after longer/more serious relationships, but usually I don't feel this way after ending something more casual, so I'm generally used to either having a little more closure or just not caring. What can I do to help myself? Would it make sense to talk with him and get some closure, even though we were only casual to begin with? If I were to talk with him, how would I approach that conversation? Any tips for other things that I can do to help me shake this feeling and understand that everything will be alright?

Can you condense the text into three sentences or less?
<bot>: Currently at the end of a casual relationship and feeling more upset than I thought I would, looking for suggestions to ease the anxiety.