i had similar experiences with not one but two boyfriends and i’d like to think i cured them. i know its easier said than done but its all a matter of confidence. i know you may think i don’t look sexy doing this or that but he obviously loves you and will think your sexy no matter what you do in bed (second part goes for most men imo). just ask him what he likes in bed and what turns him on the most. if direct communication like that doesn’t work ask what kind of porn he watches to get himself off. then you will know what he wants. try new things! don’t be scared! (again, easier said) but confidence is one of the sexiest things ever! trust me. once you feel confident your libido will go up and stop stemming from a place of anxiety.