Privacy - my private conversations and videos

I am a woman and this happened a few months back. I sent my private conversations and videos of myself and my partner to my female friend because me and my partner were having misunderstandings and i was scared of him. So, as proof I asked my female friend to keep my private files in her laptop and transferred them to her. This female friend was our mutual friend. It turned out that my female friend romantically wanted my partner so she created problems between us. So me and my partner made up and we stopped contacting that female friend. And 2 months later of this incident, me andy partner went back to our female friend's house and asked her to delete our private conversations and videos. She refused and said she already deleted them. But i don't think she deleted them. How can I legally make her delete them because the files are private and there is a risk of posting them online.