Thank you for your query. I will try and assist you as much as I can.
To bring your partner to the UK under the five year Family Life route, you will have to show that you have been living together for two years. I refer you to the Home Office policy below:
An applicant applying as an unmarried partner or same sex partner must have been living together with their partner in a relationship akin to a marriage or civil partnership for at least two years prior to the date of application and must provide documentary evidence of this. This is defined in GEN.1.2. of Appendix FM.
Dealing with your second question, under a visit visa, she must return within six months. You could consider going to Canada and getting married, or you can get your partner to come to the UK on a marriage visa: https://www.gov.uk/marriage-visa/overview
Please note on a standard visit visa, your partner is not allowed to get married in the UK or switch to a 5-year family life route. On a marriage visit visa, your spouse will have to return to Canada.
You could consider a fiance visa.On this visa, your partner can come to the UK to get married and then switch to a spouse visa. You will have to for the fiance visa that you earn more than £18,600 gross per year.
Regarding your final question, I refer you to the following: https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/452912/Family_Life__as_a_Partner_or_Parent__and_Private_Life_-_10-year_routes_guidance_August_2015.pdf
In applications for further leave to remain or for indefinite leave to remain in the UK as a partner, where there have been limited periods of time spent outside of the UK during the period when the applicant had leave as a partner, this must be for good reasons and the reasons must be consistent with the intention to live together permanently in the UK. Good reasons could include time spent in connection with the applicant’s or their partner’s employment, holidays, training or study. If they have spent the majority of the period overseas, there may be reason to doubt that all the requirements of the rules have been met, e.g. that the couple intend to live together permanently in the UK. Each case must be judged on its merits, taking into account reasons for travel, length of absence and whether the applicant and sponsor travelled and lived together during the time spent outside the UK. These factors will need to be considered against the requirements of the Rules.
I hope I answered your questions.
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