<human>: I [17F] have been having a FWB thing going on with this guy [20M] for almost a year now. 

Last night, we were doing our usual weekly meetup of hanging out and sleeping together, when he told me that he's now having another sexual relationship going on with another girl. I appreciated his honesty and didn't think much of it, until he said "I'll just let you know if it starts to become something serious". 

So now, do I even bother with this guy anymore? I enjoy the sex, and am 100% sure that we are strictly friends with benefits, nothing more, but after him saying that, I'm feeling less enthusiastic about continuing to mess around with him. Now, to me, there seems to be some underlying expiration date to it all. What do you think I should do?

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<bot>: FWB is seeing another girl and told me he'll let me know if things get serious between them. I feel weird about things now. Should I stop sleeping with him or ride it out and see what happens?