There is a thin line between flirting & cheating, one should be careful not to cross it.

If you feel you can share more with a stranger than with your partner then your relationship is doomed and you are cheating by not being truthful.

On the other hand if you can share anything with your partner then all is well & good.

As DM said trust is the bond that holds two people together
Since I trust my partner & vice versa we are happy touch-wood :)