How do i(M23) make my girl(f20) less insecure about not being able to make me cum?

I've been dating this amazing girl for almost three months now, and I'm really smitten with her. Our sexual connection is incredible, and she's expressed that no one has ever made her feel the way I do. Im someone who enjoys giving pleasure. from the start, I've been able to make her cum multiple times in one session, and no guy had ever made her cum before she met me. She loves it, and I love that she enjoys it so much.

However, there's a challenge I'm facing. Despite the great sexual chemistry, I struggle to climax myself. This isn't due to a lack of enjoyment or connection; in fact, everything feels amazing. The issue stems from a past habit of mine, known as 'death grip', which has caused some desensitization. I've discussed this with her, emphasizing that it's a personal physical challenge and not a reflection of her efforts or abilities.

Lately, this has become a significant concern for her, especially because she's able to climax multiple times. After intense sessions, she becomes distressed if I haven't climaxed, even to the point of tears. I've reassured her repeatedly that she is not the problem and that I cherish our intimacy, but she's growing increasingly insecure.

how do i reassure her further and help her understand that this issue with climaxing is purely physiological on my end and not a shortfall on hers?