I’m struggling with a boundary issue involving my girlfriend and her male friend

My girlfriend and I have been together for several years. I trust her, and I'm completely okay with her having male friends.

There's one male friend I've been uncomfortable with because he has talked to her about personal things. She has always told me about him and also told me that he has helped her a lot, which I was completely fine with.

Before Raksha Bandhan, he told her face-to-face that he wanted her to tie him Rakhi. Yesterday, he came to the house where my girlfriend lives with her three sisters, and all three sisters tied him Rakhi. She told me beforehand that he was there, so I eventually accepted it.

The part that really hurt me happened afterward. She took a photo with him because, according to her, "mera maan tha" (I wanted to). He then posted their photo on his Instagram story, tagged her, and used a romantic song. She didn't tell him that she has a boyfriend, saying she doesn't tell people because of "buri nazar" (evil eye).

I had previously told her that I'm okay with her having male friends, but I personally don't want male friends coming to her home or interactions becoming too personal. I don't want to control her, but I thought she understood this boundary.

I was very hurt and angry. She eventually messaged him asking him to delete the photo and gave him her sister's number instead of her own, which calmed me down somewhat. However, I also found out that she had deleted Instagram notifications related to his follow request/mention because she knew it would hurt me.

I'm not saying she has feelings for him. My concern is trust and transparency. I don't know whether I'm being reasonable about this or whether my insecurity is making the situation bigger than it is.

So honestly, did she cross a reasonable relationship boundary here, or am I expecting too much? What would you do in my situation?