Following my boyfriend’s ex on ig?

Hi everyone,

So my boyfriend dated a girl for 4 years and she ended up cheating on him and leaving him for a girl (this was about 3-4 years ago). *Not entirely sure if she’s gay now or if she’s bi*

She still texts him every couple months to see how he’s doing and it’s progressively started to bother me. He had previously tried to cut her off/ distance himself but she still texted him a few months later. I’m not opposed to them being friends (he’s respectfully cordial with her) since they dated mostly throughout high school and a year into college and I understand that he was there for her through her “coming out” process. However, I’m more unsure about her intentions especially since she appears to be out her long term relationship now.

My boyfriend and I have been dating for 2 years and I would like to meet his ex if she wants to continue being friends because if she’s in his life then that would subsequently mean she’s in mine too. I know this sounds pretty juvenile but I’m honestly interested in hearing the best way to go about this...

Would it be weird if I followed her on Instagram? I would never want to do anything petty but I’m aware that it might come off that way to her or I may seem jealous. I’m genuinely interested in getting to know her since she’s pretty adamant about staying in my boyfriend’s life—which again, is fine, but I would like to be involved.

Also...we’re adults so before I hear about “why would you let your bf be friends with a girl/ his ex?” He does not need my permission nor do I need his to be friends with anybody. If I was concerned or uncomfortable about someone he speaks to I would let him know.

Please let me know your thoughts and advice :)