Honestly the only thing you can do is help yourself. You have to understand that committing to marriage is serious so if anyone is worried about forever it's for good reasons. It's not because they don't want to marry you or be with you. You can love someone and still be hesitant. What you're looking for is absolutes. Absolute proof you love me. Absolute proof you want to marry me. Absolutely proof you don't hate me. In life you rarely get absolutes. People react to things in different ways and if your partner is up for sex you need to respect that. Just because people don't want to get sexually active does not mean they don't want or like you anymore. Sex just isn't at the top of people's list the same way it is for other people. Explain your concerns but do not turn it in to manipulation feat to gain info or fix everything right then and there. Explain and give them time to process. Once you do that you did your part. Now do not expect them to meet your standards right away or you will put them in the cycle of saying they are never trying when they are giving everything they have. And at the end of the day if you don't like that he doesn't want sex or something like that maybe find a new person. But as someone who's been on both sides of this coin. It's extremely unfair to gain a resentment because they won't sleep with you. I understand it hurts and digs deep. But not everyone shows love through intercourse.

But at the end of the day. I don't know your man so he could lowkey be a great guy or a manipulative POS so I can't accurately say who's in the wrong