Cheating is defined by the expectations of the relationship. If your relationship is defined by being mutually exclusive, then yes. If your relationship allows for you to experiment with a girlfriend, then no. Most relationships are built on unspoken expectations of their partners and that's what causes the problems in the first place. Just be open and honest up front and you'll have a lot less heartache, of course you may have a lot fewer relationships too.
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but what can ya do.
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