No of course you can't make someone fall in love, but most mothers wouldn't act the way Carole acted.
The Middletons financially supported Kate for ten years, so that she'd always be available for William when he wanted her. When William broke up with Kate (and a whole club full of people saw him jump on a table and shout "I'm free"), Carole threw a party and invited him, to help them get back together. Paying thousands for Kate to join the same expedition in the same village in Chile that William was currently on. Letting Kate drop out of her place at UoE and apply to St Andrew's instead.
A lot of you must have daughters. How many of you would financially support a healthy able-bodied daughter and let her sit on her arse for ten years waiting for a bloke to call so she'd be able to go running whenever he snapped his fingers? Surely most mothers would say, no, get a job, build a career, develop your own interests, don't let your whole life revolve around a man.
If your 25yr old daughter was dumped and publicly humiliated by a bloke who'd been stringing her along for years, would your response be to throw a party for your daughter's ex-boyfriend, so you could try to convince him to take her back? If a bloke had done that to me, my mum would have never let him back in the house unless he grovelled!