My (25F) brother-in-law (20M) proposed to "Tanya" (20F) after 2 years of dating. Tanya will took my BIL's lastname, I did the same when I married my husband (26M) last year, before marrying I didn't have a personal instagram account (i don't really use social media) and I just used my husband's account if I needed it.
But after our honeymoon I created an account to post the pictures and I choose "mrs[my husband lastname]" as the handle. Now I have 79 followers (friends, family/in-laws and co-workers), 11 posts and I post some stories once in a while, I mostly use it to watch reels and keep updated on my favorite celebrities.
Well, last week I was helping Tanya with her wedding gift list and she asked me to change my IG handle to give it to her as the gift and that it will mean a lot to her, I suggested that she can just add a underscore, a period or even numbers and she said that it ruins the "username aesthetic" and that she never used it because she hates it.