Ultimately, it’s up to you what you do, but a lot of people are reeeeally uncomfortable with people who identify as lesbians while dating men, and understandably so. I’m not saying you have to break up with him, but you should definitely do some internal examination of your identities and relationship.

yeah, lots of lesbians include woman-aligned nb people in their attraction, and there are a number of lesbians who identify as nb themselves. unaligned people are more of murkier subject - it’s easier to define lesbian as woman/woman-aligned people attracted exclusively to women/women-aligned people, but there ARE some people who just consider themselves unaligned and a lesbian (or define themselves in a sort of “my gender is lesbian” way) and unaligned people who are comfortable dating lesbians, while there’s others who aren’t.

of course! it's a common experience but not everyone significantly feels it

Its not an easy situation, and I’m sorry that you’re having to deal with it. It’s incredibly unfair that you have to hide such an important part of yourself to keep her happy. Again, don’t feel pressured to come out if you aren’t safe or simply if you don’t want to... but refusing to act on being gay isn’t going to make you happy in the long run.