Oh, c'mon, I took you to be more intelligent than you appear to be.
Sheila had been materialistic. Why a property in Maida Vale ? Wasn't a cottage in the same village as her family good enough ?
It seems that while living with Colin she wanted her own way or threw a strop along with pots and pans.
In her younger life her parents bent over backwards to find her and fund her the job which she wanted and even that didn't seem enough. Parents funded her trip to Japan which was a waste of time and money. In the end Sheila didn't have to work. Wouldn't we all have loved such a life ?
Given that Nevill bought the flat, he was hardly going to buy somewhere in the 'wrong' address because it wouldn't have been somewhere he wanted Sheila to live, apart from which London, per se, was where her life was, an NO! absolutely NO! She most definitely didn't want to live near her parents.
Colin doesn't strike me as being the argumentative type, however, I believe there probably existed between them, a war of attrition. He'd walk away. Sheila would be determined to get his attention. Utensil got hurled. Why would you claim she wanted her own way?
I think you'll find that the Japanese job may have have been part and parcel of her modelling course. Had it been a success, it would have led to more assignments -I believe it was from Japan that she made a request to see a psychiatrist?- Certainly, like all her health care, it was funded by June and Nevill. As was the failed secretarial course, and the failed hairdressing apprenticeship. It's what parents do. She could hardly have been said to be living the high life when she ended up as a cleaner. NO! I wouldn't have like her life.