how long have you been together and what is your nationality?
your partner should apply for UK residency as soon as possible without leaving the UK on form FLR(FP)
The application is complicated and I would suggest that you retain an immigration lawyer to assist with the application as this is an online service and you need someone to look at the paperwork.
if her application is successful, she will get UK residency and she does not need to return back home.
all the best
I would repeat again that the application is likely to be complicated and you should engage a professional person to assist you. I am not available to,speak on the phone unfortunately.
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