@Natw22 your partner does seem to be emotionally invested and finding it difficult, and I wouldn't want to disregard that... but at the same time I wholeheartedly agree with others: IVF is mostly women's business.
My DP had 50:50 say in whether we were trying for children. He never had 50:50 say whether we had IVF as part of trying, because I went through that, it happened to me. He was quite against the idea at first, but I'm glad I pushed ahead. He wanted children, and as the hardship of IVF fell so heavily towards me, I thought the least he could do is go along with it.
I also have to add that on the whole, infertility is also women's business, even when it's male factor. Yes, a man may be desperate for children too, but it's often the woman who finds herself asked about it constantly, on the receiving end of countless comments, gossiped about, left behind socially, bombarded with babies and baby talk from friends etc. It's also women with the ticking biological clock that severely limits our future possibilities.
I will say though that, if after years of many rounds a person wants to move on and try to look positively at a different kind of future, then that's fair. I think that's why it's important to discuss upfront how long you're willing to try and agree a plan together, but I would expect that plan to take into consideration that the woman is more affected.