Catch her in her own game. Tell her that if she wants a break then you assume that means you are free to date others and you just want to make sure that's okay with her, because there are plenty of opportunities where you are going. If she says it's okay, break up with her completely right away. It's better to end it now than when she cheats on you.
Don't cry, don't regret and don't blame
Weak find the whip, willing find freedom
Towards the sun, carry your name
In warm hands you are given
Ask the wind for the way
Uncertainty's gone, your path will unravel
Accept all as it is and do not blame
God or the Devil
~Born to Live - Mavrik~