I’m a 55-year-old woman, and have always had a pretty happy sex life. But lately, it’s getting harder for me to come! Right when I am “on the verge,” I lose it and have to work up to it all over again. This doesn’t happen when I masturbate, just with my husband. We’re both frustrated. Lube helps a little but not much. Suggestions? Supplements? This is getting very annoying. Thanks.