(((BNLsMOM))) - I'm sorry you're in this difficult and awkward situation. Do you know if he looks at porn? Is this a laptop that you use as well - so you could search recent history? Many men do look at porn and self satisfy - some women don't mind and others consider it a form of cheating.

The best way to approach this, is calmly. If you use anger or corner him - he'll either lie or get very angry so you'll back off. He'll automatically become defensive if you approach him with anger. Take some deep breaths and think before you act or say anything. This needs to be handled delicately in order to get a straight answer.