man im sorry to hear. bro im no expert but if you really want to salvage the "friendship" just tell her the how u feel and that one nigh of hooking up you wouldnt want to ruin ur "friendship". note i say"friendship" because well its a friendship, not a friendship with benefits. but bro thats what i would do in my case. perhaps someone else might do it another. this also depends if u really wanna make her u gf or vice versa but best of luck to you and things will turn out better for u if you believe it

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cheers!