She seems like more of a passive, let it slide, type person. Not saying that's a bad thing.

No need for rush.. It seems like there is a big history between Cora and Rumple. I think when she got her memories back, it will be much bigger reaction when she finds out about their past....

I don't no if she'll necessarily be ok with it...but I can't see her going into "major catfight" mode. I think as long as Rumple explains the reasons and that Cora kissed him and not the other way around...as long as he's actually honest with her (for once) and she doesn't end up finding out some other way first.

Belle has a pretty understanding and forgiving personality, and Rumble had his reasons, so im pretty sure she'll just let it slide, and i really cant imagine her getting into a major cat fight, so i definitely wouldn't pick the other option.

Cora kissed rumple I think he is totally faithful to belle so she would forgive him it's in her nature

It was a long time ago