According to the basic principles of metaphysics, ideas technically exist even though they are not tangible. Thus, abstract concepts like justice and goodness are real even though they are not tangible. It goes back to the Platonic distinction between image and form: a picture of a circle is not an actual circle, which in its perfected form only exists as an abstract ideal. Reality, according to the metaphyiscal view point, encompasses all of that which we recognize, including both the material and the immaterial.
Consequently, though your waifu is immaterial, though you will never touch or hold or embrace your waifu in any material sense, as a metaphysical concept your waifu is, technically, real.