My husbands family tells him everything

Everything I put or do on social media I guess I had vented on fb years ago & they just told him this. Whatever conversation or text I had with his mom or anyone their telling him all of it. I feel like this is toxic & insane? Is this normal, do people do this? I'm exhausted & scared to tell anyone anything now. I dont do this to anyone, it's like if my sil vented to me about my brother then I tell him years later what she said. I dont even have the capacity to even remember everything. Any thoughts?