A great romantic hero wasted on an utterly stupid, vapid, bratty, flighty, did I mention stupid?, immature, rude, entitled, stammering, weak, did I mention stupid?, thoughtless, superficial, self-pitying, co-dependent, did I mention stupid heroine?
H and h are step-siblings although not related by blood and they never really had a sibling-like relationship due to their 13 year old age difference.
She hero-worshipped him until inevitably getting the requisite schoolgirl crush on him when she was 18. He felt the same but never let her know, rightly so, as he felt she was too young and immature and he didn't want to take advantage of her hero-worshipping but wanted to let her grow up, live her own life, and get to know who she was, independently from him.
Trouble is, this girl never grew up! She had the Peter Plan complex. Despite the best education, lifestyle, and opportunities that money could buy, money provided by the H, she drifts through life, playing at jobs instead of engaging in any serious academic or professional pursuit. Basically living the idle life of a rich socialite until she meets a weaselly, social climbing fiance who is very interested in the high class lifestyle that her allowance is going to make him feel accustomed to. The type of stupid heroine that I really can't identify with or root for, unless I see some sort of evolution in her personality over the course of the story. This was not the case here.
Hero puts the kibosh on the h's engagement, naturally, and heroine has a rude awakening, realizing the fiance was after her money only and to give her credit, she promptly ends the relationship.
She also realizes her lifestyle has not been supported by her deceased father's worthless trust but anonymously by the H. Her reaction to this turn of events is wildly immature, over-emotional and drastic. Feeling humiliated to be beholden to her step brother, rather than grateful and humbled at the classy way he has enabled her to have the best of everything without making her feel she was indebted to him in any way, she lashes out at him, wants to sell everything she owns to pay him back (very insulting gesture towards an incredibly generous and selfless act) and of all things, wants to embark on a career as "high class" housekeeper, basically the equivalent of a female butler running the gigantic households of the London upper crust. With zero experience, zero work ethic, and one hundred percent sense of self-entitlement! Stupid doesn't even begin to cover it.
Hero spares her the humiliation of self-destructing and instead he generously offers her an opportunity to become an executive chef for his company instead. Again, there is a lot of lashing out, suspicion, anxiety, wishy-washiness and hand-holding required by her. So what does she do once she gets acquainted with her job? Promptly start dating the company lawyer.
I mean, she just came off a terrible relationship that showed her just how bad a judge of character she is, she has been given a golden opportunity to stop paying lip service to the idea of standing up on her own two feet and acting like an adult, and instead of focusing on herself and her new, demanding job, she just starts dating someone in the company, unable to comprehend how awkward things might get with office romances, and oblivious to the disapproval of the H. *sigh* Stupid, much?
All the while of course, there is serious sexual tension between h and H, including a nighttime bedroom romp initiated by the heroine loudly banging on her window in the middle of a storm because the dumbass couldn't locate the latch that kept the window from being shut. Did I mention h was stupid? *face palm*
As for the OW in this story, despite the heroine being told by everyone that she is a nasty liar, the heroine nevertheless accepts everything the OW says about her supposed long-standing affair with the H. When the hero returns from a trip, instead of confronting him with the OW's lies, h runs headlong into a tsunami-sized wave in the ocean, necessitating a hospital visit for both of them. WTF? Who does that?!!! Wait, did I mention the heroine was stupid?