It's not weird Shaughna likes Luke M, she even explained the feelings have grown. It's very natural to just view somebody as a friend but fall for them after you get to see their personality bloom - the public have done the same with Luke M actually, he wasnt that popular to begin with but his popularity is growing because hes a nice, genuine guy.
Mike literally went from saying he wanted Sophie, then to Jess the same episode and saying he liked her so much he would leave into dumping her for Pracilla all over about 2 or 3 days
