If you fast travel to the house she is living in you will sometimes see Faendal leaving the house after visting her. Even if you don't live in Riverwood he still will vist her. It's all good.
If Lucan dies, Camilla will take over the store. She is involved in a local love triangle as the love interest of both Faendal and Sven. She may be married if her disposition towards you is high enough, giving you full access to the Riverwood Trader. She wakes up at 7am for a one-hour breakfast, then starts working at the store for ten hours.