The only time Jana feels safe is with Gunner and the bike club, which is ironic since every one of them are violent and have broken the law. At any other time, she might have felt fear, but this wasn't a normal situation.
Gunner didn't want a relationship. Sure, he kind of envied the brothers with old ladies, but he didn't know if he had what it took. His brothers spent a lot of time looking after their women because they tended to get in trouble a lot. He doesn't think he has a choice but to help Jana, but he certainly didn't intend to fall in love with her.