Rumple does actually love Belle. He might be more worried about what she’d do to herself than her finding out about the lies. He’s taking a gamble on those, and he knows it, and probably believes she’ll either forgive him or leave him eventually no matter what happens.
But even if his desire for what the hat can give him is strong enough to make him choose it over being honest with Belle, he does love her and want to protect her. He’s not just in this for self-preservation, even if that is a strong part of who he is.
I realize that S4 has only given us three scenes that weren’t cut to actually see Rumple’s softer side, so it’s easy to assume he’s lost it completely, but I still see it there. He might not put Belle ahead of his goals with the hat, but he’d definitely do anything else to protect her.
Keeper of Belle's Gold magic, sand dollar, cloaks, purple FTL outfit, spell scroll, library key, copy of Romeo and Juliet, and cry-muffling pillow, Rumple's doll, overcoat, and strength, and The Timeline. My spreadsheet: https://drive.google.com/file/d/0B6r8CySCCWd9R0RUNm4xR3RhMEU/view?usp=sharing