We ran into the same issue. Sex was maybe once a month, maybe twice here and there. From the male perspective the biggest thing was learning to learn to hold back. When you feel like your getting to your breaking point back off and slow down for a breif moment and then get back into it. After a while of doing so you'll learn to have more self control. Worked here. We went from a couple minutes to her having multiple orgasms and me lasting over 40 minutes. A lot of it in my opinion is mental.