She had plenty of chances to bring up her feelings to him, she just resorted to fortune-telling in hopes he would ask her out, not realizing their feelings were mutual for a time.
The otaku may be lacking self-esteem thinking she was too good for him to move onto someone else, but she's also partially at fault for not approaching him sooner. Tragic as this is, she needed to learn the hard way what not acting at the right time would do to her.