My thought in regard to the SR comment is - how obsessed are you, really? If you are spending hours upon end (or even intermittently) posting and reading, whether on your computer or phone, that could be an issue.
As you have a good relationship otherwise, I'd suggest asking her what would make this online fascination less bothersome for her. One thing might be to stay in the same room with her while you are online. Maybe she can get her own account and read your posts (if you're comfortable with that)? Perhaps you can limit your time to say... I don't know, 15 minutes in the morning and an hour at night?
People have been known to develop inappropriate relationships online (present company included), so minimizing the appearance of stealth is important.
Just my thoughts...
O