I can absolutely relate to your situation.
You just described my marriage to my ex-wife to a tee.
Basically a very good woman and we were great friends.

But I too never actually felt that I was "in" love with her.
(And I never really felt she was in love with me either.)
I knew it that back then as much as I know it now.
I ignored my feelings, even while we were dating.
I also hoped I would "learn" to fall in love with her.
And I bet the feeling was the same on her end.
We really did get along so well on so many levels.
But something just didn't click romantically.
We married anyway. Maybe we were too young, too insecure
and merely "settled" for each other. Or maybe we were only
meant to be friends and not romantically linked.
To this day, I don't really know. But I do know our foundation
was extremely weak and was destined to crack, which it did.

I never cheated, but eventually I'd find myself daydreaming
about other women because of what was lacking at home:
true love, intimacy, communication. Is that happening to
you as well?

But enough about me. This thread is for your benefit. I've
only described my marriage to illustrate how I didn't face my
true feelings while my inner voice was screaming out for me to
do exactly that. I strongly suggest you face your feelings now.
It's really unfair to both of you to continue if something is
just not there for you. You shouldn't try to force your feelings
(as I did). Again, unfair to both of you in the long run.

Keep in mind that I am NOT by any means suggesting
you break up. But I do strongly suggest talking to a therapist on
your own to sort out all your feelings (and lack of feelings).

Like I said, I can totally relate to what you're saying.
And I'm sincerely sorry you find yourself struggling with this.

Please feel free to PM me if you'd like to discuss further.