Props for listening to marvin gaye

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The problem may be one of a few things -
-You are too nice to her
-You are too quite
-You are too predictable
More likely than not, since you've said she doesn't put in effort, it is her fault as well. Obviously shes not a keeper, but in the meantime, do some wild stuff. Grab her by the ass one day and kiss her passionately. Give her some stuff to rub her pvssy to afterwards. Bring up some convo topics that will involve both of you.
Giving a little less respect, in your situation, will be benefitial.