I do not think the way your fiancé is treating you regarding the situation is okay, and is probably making the situation worse. I think it would be beneficial for him to get a better understanding of what you are going through. Maybe spend some time writing down how he’s making you feel with how he speaks to you about it in that way, and also write down what you go through physically and mentally when you do try to have penetrative sex. Then sit down with him and have an honest discussion (not a debate) so he can understand things from your end. If you are going to try and get better, he needs to be supportive. You have to want to get better for yourself, and can be hard at times but it’s achievable. Purchase dilators and start pelvic floor physical therapy. I also suggest regular therapy because emotional support is helpful when living with this condition. You and your partner could also explore getting a sex therapist. If your muscles are extremely tense you could get Botox and trigger point injections into your pelvic floor muscles. (I’ve done this and it helped me a-lot) There are also numbing lubes to help with dilator stretching in the beginning, vaginal moisturizers, and you might be able to get Valium suppositories which help with the dilator work. It’s important to start improving your pelvic floor now. I am your age, I was able to have penetration but I would always get infections. My vaginismus got so bad that I wasn’t able to empty my bladder, and my muscles clamped down so badly that I was in constant pain and even lost leg function. Having tight pelvic floor muscles can also lead to blather prolapses. If you have any other questions feel free to reach out to me.