i dont think there has been that many posts on here where the wife has returned to the fils becuase she is homesick, but a problem with coming on a fiancee visa is, you have to wed within the 6 months and i would have thought it could take longer than 6 months to see if she couldn't live here (with the excitement of visiting a new country, planning a wedding etc it might take some time for the 'honeymoon period to wear off), thou that 6 months should give her a good idea
my stepson (was 18yrs old) the first time he came to the uk, was homesick within months of coming here, he went back to the phils to go to uni, but he returned 2yrs later and has been here a yr and thou he is married now (not seen his wife, 2yr daughter and 4 month old son! for the last year) hes handled it very well, alot better than last time, thou hes off to the phils next sat for 3 wks, he sees his and his family future here in the uk and not the phils,,