Not crazy, no loss of reality. There's no evidence of either. Tuvok used a holographic wife to get through his mating crisis, and no one concludes that about him.
In Endgame where is Tuvok when we first see him?
In the
mental health care hospice, he is.

Admiral Janeway throughout that episode is also plainly insane.
Now jou're just doing a syllogism. (I expected more rigour from you.) "Tuvok is insane in the future*. Tuvok used a holographic mate. Hence using the holodeck to satisfy one's libido is proof of insanity."
Man, they all do it in Star Trek! They just don't advertise it. What is more crazy about a holo-lover than a moment of imagination-fueled masturbation? Not everybody has the luxury of having an emotional connection with a real partner. Fantasy can be a big part of what keeps somebody from depressing. Having a rich imagination or an effective suspention of disbelief is not yet considered insane, to my knowledge. Or half of humanity is.
And, do you have a phD in psychiatry, for being that categorical? You've accustomed us to better shoring up of your arguments.
I consider myself sane and I would have gotten lost in that relationship much more than she did. Especially when it turns out that a hologram can turn into an actual person, like the Doctor. There's a big debate on the status of holograms. In the possible epilogue we can see in another episode, the Doc is married to a real person. People are surprised, but not shocked.
*due to an illness that developed over many years, by the way.