I can't make my boyfriend horny?

My (F24) Boyfriend (M25) and I have been together for just under a year. The first half of our relationship was long distance, with a lot of sexting. I was excited to get with him irl since we seemed to share a lot of kinks.

For the last 8 months since we've been living in the same town, we have had sex less than 5 times. I have tried point-blank asking, costumes, talking through what he wants, telling him what I want, making absolutely sure he's heterosexual.... literally everything.

Before, I thought the stress of his fast-moving job was giving him ED. Then I figured it was his new depression meds. But he's gone through an entire adjustment period, and still no dice for me. We had sex for the first time in 3 months a few weeks ago, and I struggled to enjoy it because I kept wondering, "when will this happen again?"

He has assured me time and again that he loves me and finds me attractive, and I feel the same about him. He's just as mystified as I am about why I can't turn him on - it's definitely not a communication problem.

We think he has Low T. Anyone have experience with this?? I just want to get fucked by my partner, so what can I do?