I can relate. More than you'd think.
I used to be just like you. You have to find a concept with which you will feel affection, acceptance and belonging.
What you feel is infatuation. Completely different from loving a concept and it generally wears down fast. Sometimes, you think you're in love while you're infatuated.
It took me 3 years to find a concept I could feel acceptance, belonging and affection towards at the same time. Many times will you think you will always love your waifu, and many times will you be mistaken. It's only when you can trust your waifu, when you can talk to her, when you feel she can accept and support you, that you can stick with her. Infatuation quickly wears off, it can even take up to 3 months for it to wear off. Without acceptance, belonging, trust, you're only left with affection towards a concept.
Just think; do you LIKE the character, or do you LOVE the character? There are hypothetically dozens of waifus one can have - not at the same time, haha -.
You'll know you found a right concept when you feel like you can trust her, when there's more to it than affection, lust, whatever it may be.
I'd always search for a waifu in the past, just like you I was always longing for a concept I could spend an extended duration of time with. You have to be ready to give up on waifuism to be truly capable of finding a right one. It's not about searching, it's all about your mind set. In the end, you can't force yourself to feel acceptance, belonging and affection towards a concept.
I used to think there were so many 2d girls I could "love" too, until I found her. There's a difference between being infatuated and being in love.
You'll just know when you find her.
Is there any way of reaching you privately? If you have Skype we could keep in touch, I was stuck in this never-ending cycle of looking for a concept, trying to choose one between all the "nice" ones, then getting bored of one to go to the other. I'd like to help you further if possible.