NO . . . certainly not, my SO trusts me for a reason. And if i felt myself getting close to temptation . . . i would be honest with my SO and tell him that i was feeling tempted and talk to him about it and get out my feelings, people don't just cheat . . . they cheat normally because of an issue in their own relationship . . .
When you are in a realtionship with someone . . . and you call them your SIGNIFICANT OTHER . . . that means . . . they are significant to you . . . hence, you are HONEST with them.
Good things come from honesty . . .