Which Good Samaritan can help this lady

From my inbox (Reggae : SEX STARVATION)

How do I deal with sexual frustration and starvation as a Christian wife? We have been married for 6 years and blessed with one child.
Our dating (3 years) and early marriage years were on long distance. My husband was great in bed then until about three years into marriage. Things just changed. We have sex mostly when he wants it, he lasts for a minute or less and he is out (rarely does he even get a full erection). We have not kissed in the last three years (he has dental condition which he refuses to seek help for. He was seeing a dentist but stopped treatment midway). We have not had any other sex style apart from missionary. Basically the little sex we used to have is non-existent now.
About the erection issue, I thought it was because he gained weight and so I suggested he works out. He felt disrespected, controlled and manipulated by my suggestion. I started looking into what and how much I served him, like I would offer nduma and sweet potatoes instead of the bread/chapati/cake/mandazi which he loves. But he refused to take them saying he dislikes them. I talked to him about checking his food portions then (especially starches) because he is anti-exercising. That was not welcome too.
I have calmly expressed to him many times about how I feel about our sex life. He has never acknowledged my feelings or admit maybe he needs or we need help. I suggested to him we seek professional help, but he is not for it. He thinks I am the one with a problem; that I am not being submissive (because he provides for us so he doesn’t see why I keep complaining about sexual satisfaction).
I am losing it, and I don’t know what to do. I would like to save my marriage seeing as we are still a young couple, but I am so so frustrated.

Mwambie atafute kaben10 kamtoe nyege

Ukame ni mob kwa hizi ndoa. Kila mtu akichukua benten hawatosha.

Siku izi wako wengi kupita kiasi

There are no good samaritans on doshi matters. She must find a master to take her on a crash course on the art of seduction.

She is either stupid or naive, that man of hers has a side dish, and simply isn’t interested in her anymore… she needs to find her own discrete outlet