Not on his social media?

Been dating exclusive for a year, met his family, some friends. His ex girlfriend was on his social media, he tagged her and she tagged him. Photos of them on holiday for his birthday etc, other holiday photos. Relationship was stormy lasted about a year, ended on a bad note. We have had 12 good months, no arguments, getting on well, been on holidays etc. He will post photos of him with my dog on his FB page, but no mention of me at all. No photos of us together on holidays, status still says he is single, I dont exist on Social media, but he is okay in person and in our home town - no problem at all with introducing me as his partner IRL. He says he has had problems with social media in the past, nastiness etc, and he doesn't want his ex causing me any hurt or harm, but my attitidue would be "she doesn't matter". She has looked at my FB page, and so have her friends (i was told by a friend of a friend) but I have never met the ex though and dont know her). I just dont understand why he was happy to post photos of him/her (in a not so good toxic relationship) but with me (good relationship) I dont exist. It is causing me doubts and insecurities, but he is adamant he wants to keep things private. Why would he be okay IRL but not want me acknowledged on FB. I have asked him but he just says "Privacy". I see him most every day, he rings me every morning, and evening, we exchange texts during the day, but not excessive. No red flags there, and he is always there for me if I need him. So what gives?

Updates
1 y
They do have mutual friends still
Not on his social media?
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