As long as you have solid proof that you have cohabited for at least 12 consecutive months (looks like you do), you're good.
[source]
https://www.canada.ca/en/immigration-refugees-citizenship/corporate/publications-manuals/operational-bulletins-manuals/permanent-residence/non-economic-classes/family-class-determining-spouse/assessing-relationship.html
In the case of a common-law partner, documentary evidence should include:
- a completed Relationship Information and Sponsorship Evaluation questionnaire (IMM 5532) (included in the application package)
- proof of separation from a former spouse if either the sponsor or the applicant were previously married
- a completed Statutory Declaration of Severance of Common-law Union form (IMM 5519) if either the sponsor or the applicant were previously in a common-law relationship with someone else
- if the principal applicant and sponsor have children in common, long-form birth certificates or adoption records listing the names of both parents
- photos of the sponsor and principal applicant showing they are in a conjugal relationship
- at least two of the following sets of documents. If the sponsor and principal applicant are unable to provide documents from a minimum of two of the following sets of documents, a detailed written explanation must be provided:
- important documents for the principal applicant and sponsor showing they are recognized as each other’s common-law partner (such as employment or insurance benefits)
- documentary evidence of financial support between the principal applicant and sponsor, and/or shared expenses
- other proof that the relationship is recognized by friends and/or family (e.g. letters from friends/family, social medical information showing a public relationship)
If the sponsor and principal applicant are currently cohabitating, evidence from at least two of the following sets of documents showing that the principal applicant and sponsor have been living together for at least one year (e.g. documents showing the same address for both). If they are unable to provide documents from a minimum of two of the following sets of documents, a detailed written explanation must be provided:
- proof of joint ownership of residential property
- rental agreement showing both the sponsor and principal applicant as occupants of a rental property
- proof of joint utility accounts (e.g. electricity, gas, telephone, Internet), joint credit card accounts, or joint bank accounts
- vehicle insurance showing that both the principal applicant and sponsor have been declared to the insurance company as residents of the insured’s address.
- copies of government-issued documents for the principal applicant and sponsor showing the same address (e.g. driver’s licenses)
- other documents issued to the principal applicant and sponsor showing the same address, whether the accounts are held jointly or not (e.g. cellphone bills, pay stubs, tax forms, bank or credit card statements, insurance policies)
If the sponsor and principal applicant are not currently cohabitating, evidence must be provided that shows the sponsor and principal applicant cohabitated for a minimum of one year in the past, and the following must also be provided:
- proof of contact, including letters, printed text messages, emails or social media conversations, or other documented proof of contact between the principal applicant and sponsor. A maximum of 10 pages should be provided
- proof of the sponsor's visits, such as airline ticket coupons or used boarding passes, photocopies of pages of passport for your sponsor showing entry-exit stamps supporting visits, etc. If the sponsor did not visit the principal applicant, an explanation must be included in the principal applicant’s IMM 5532 form (Part C, question 4)
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Don't `overthink' things in terms of proof; focus on quality versus quantity. Sending 20 pictures from the same event, for example, will not prove much...other than you were together on that day, right? If for some reason IRCC needs more evidence, they will ask for it. It would be helpful to get a couple of letters from those that know that you're `still together'. You probably will need to include form IMM 5409E - Statutory Declaration of Common Law.
Good luck!