Dryness??

So my boyfriend and I have a very good sex life. I am super attracted to him and have the ability to get wet relatively easily with him, but when we have sex for longer than like 15 minutes I go dry. It's very frustrating and makes him feel bad. Could this be caused by stress and trauma? My anxiety has been at an all time high the past few weeks and im sure it has something to do with my mental health. Any suggestions?