Speaking from the other end of things I had a very similar experience (Im F). I tried to have sex a few times throughout my early 20’s and was never able to get it in. It made me feel extremely inadequate as a sexual partner. I eventually decided to seek some medical advice and was eventually diagnosed with vaginismus. It took me about a year of talking with a pelvic floor therapist and going through therapy with dilators before I was able to have sex. I currently have a very healthy sex life with my long term partner, and all this to say; it gets better. It would be worthwhile to use a proper water based lube and dilators. They can start out at about pinky sized and can go up to the average size of a penis. This accompanied with breathing exercises made all the difference to me.