You're wondering whether your hormone therapy, designed to address your hot flashes, is having an unintended negative effect on your libido. The good news is that adding estrogen is better for sex, in general terms. So you don't have to take back your hot flashes to get your libido back!
The less good news is that libido is sometimes a puzzle to solve. I've found that non-oral estrogen addresses hot flashes with fewer unintended effects on sexual desire. The reason is that oral estrogen enters our systems in ways that affect metabolization in the liver and resulting circulating testosterone levels. And testosterone, though not entirely understood, is as important to women's sexuality as it is to men's!
You might start by changing to non-oral or transdermal estrogen; it will likely take up to 12 weeks to see whether there's an effect. And if that doesn't make enough difference, there are other options you can explore with your health care provider.