I’m a 21M, and my gf 21F, have been together for two years. Our first sexual experience was painful for her, and since then, her excitement kept decreasing. She avoids sex due to pain and a burning sensation around the walls. We’ve tried different solutions like lubrication, longer foreplay, and various positions, but nothing helps. We use water-based lube because gel ones cause pain, but it evaporates quickly and I failbto realise due to condoms, leading to friction. She hasn’t ever inserted fingers or any toys during self pleasure so she doesn’t know much and avoids discussing our issues because it reminds her of pain. I have tried giving her time to open up and waited patiently for months, nothing changed. It’s affected our intimacy, leading to arguments.
I want her to enjoy sex, not just do it for the relationship.
More detail in comments.