This question ranks very close to “Honey, we need to talk” in my personal list of worst openings for a conversation. And here I am, musing on the same question for a second time.
Read my takeaway here: : https://valentinathoerner.com/blog/do-you-think-we-are-happy
Minimalist Musings in Mataró 
Hope everything turns out well for both of you!
I don’t remember where I’ve read it, but I remember a theory that living in nuclear families puts simply too many expectations on both sides of marriage. A hundred years ago marriage was more of a business agreement than an eternal communion of souls we’d like to believe in. Romantic love, great sex, or even friendship were not required, as people looked out to fulfil these needs elsewhere (also, they probably didn’t have much time to think of such stuff, as most of their resources were simply spent on survival).
Now that we’re free to choose anyone we want as our spouse, and we don’t spend that much time with extended families, we expect our partners to fulfil all of our needs. They should be the perfect soulmate, best friend, passionate lover, caregiving parent, therapist, stylist, chef, spiritual guide, career consultant, and share our deepest passions, interests, hobbies, and music taste. If some of these areas are not satisfactory, many people believe the relationship is flawed.
If neither of you feel happy, perhaps there are some expectations in your marriage that the other one can’t or won’t meet? I’m the last person to give advice on relationships, but getting clear on this area – what I expect from a potential spouse that’s absolutely crucial, what expectations I’m ready to accept – has helped me solve many of my troubles. Not all needs will be ever met even in the most satisfying relationship, but it looks to me that even very non-standard setups can work out, as long as both sides have consistent expectations. Physical presence is a deal breaker for me, but I know couples thriving in long-distance long-term relations.