Ladies I need help ASAP (sex deprived)

I don't know what to do. My boyfriend and I are both 18 and have been together for 3 years. We have always had an active sex life (at least 4 times a week). But something has changed these past 6 months. At first I understood why. "Its boring," he said. I got that, so I offered him up chances to use some of our toys and try new positions. "I dont know what I like," he said again. I tried explaining to him that's why we try new things together, but still there's new excuses, in my opinion. This doesn't feel normal for a healthy 18 year old Male. I've given him chances to try new things, I've initiated sex like he wanted, I've pulled my hair back how he likes, new toys, more flirtation on my side, and yet we have only had sex three times since Valentines day; all of which I was very unsatisfied as he doesn't like foreplay. Am I being unrealistic? My self esteem has gone way down because of this and I've cried nearly every night. What am I doing wrong?