Ex's and promises....?

Its pretty frustrating when you make amends with an ex and you're on 'good terms' but doesnt pan out the way its supposed to....we made a 'promise' to keep in touch and keep up with each other, because the significant situation we both have makes it pretty easy to not be more then friends anymore. its just irritating that she was the one complaining about 'I dont want to lose our friendship etc etc' and 'I'd hate if we were to stop talking blah blah blah' so ykno, i was like sure why not, we can be friends and she's almost completely ignoring me, and we both have a middleman friend who shouldnt be, but is basically our messenger, i dont think thats fair to him. anyways, we settled on being friends and now she's ignoring me?? and i dont want to just not talk to her cuz i know as soon as i stop tryin to talk to her she'll want to talk....its just like wtf?!?! i dont even really want to be friends but we cross paths a lot so it'd be awkward if we werent....am i trippin or wat the eff?!