This seems to all tie in with the prospect of seeing Ts house and family during the construction, which led to many feelings trying to push up to the surface. When the idealization defenses are diminished, you don't focus on the 'other' so much and are left with your own feelings of unrequited love. Your T seemed to allow a slow process over the years (rather than abrupt) and so you've developed a strong relationship, so I think it will be ok.

You have a good and steady T, so things will be good. Both my long-term Ts worked with the unrequited love; one handled it well one did not.