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No, affidavits are considered weak evidence. Focus on stronger evidence of time spent together in person, such as passport stamps, boarding passes, receipts indicating you were together at the same location. Support with some photos of the two of you together at different events, along with photos of you two with friends and family.
Our bona fide relationship evidence was just 12 pages, mostly consisting of passport stamps from our vacations and our photos together. We had no joint property, no leases, no children together. We didn't submit any 3rd-party affidavits. Our petition was approved without RFE.