What you describe—pain and a burning sensation around your clitoris—is most consistent with vulvovaginal atrophy. As we lose estrogen, the genital tissues thin, and the labia and clitoris actually become smaller. There's also less blood supply to the genitals. Beyond making arousal and orgasm more difficult to achieve, these changes can also lead to discomfort, and experiencing pain when you're looking for pleasure will certainly affect your sex drive and arousal!
Localized estrogen is the option that works best (and it's often a huge difference) for most of my patients, restoring tissues and comfort. Talk to your health care provider about the available options and what you might consider in choosing one.
A vaginal moisturizer can also help you restore those tissues, but I suspect you'll find that most effective in combination with localized estrogen.
Please do take steps to address your symptoms! If sex can be more comfortable and enjoyable for you, I'm hopeful that your sex drive will rebound.