Finding My Boyfriend Pays For Porn

I opened my laptop to see my boyfriend's emails. He often leaves things open after he's done, as do I, as I thought there was nothing to hide. This time I see an email confirming a porn subscription had been cancelled. From there I looked to find he used to subscribe to Snapchat porn etc before we were together (doesn't bother). However with this he subscribed once we had been together for over 8 months, and we've just crossed 1 year.. We spoke about it and I explained how worthless it made me feel that we're not very intimate anymore and then I find this and my confidence plummets... He doesn't understand how I feel that way.. is this normal? Am I overthinking? Thoughts ladies?