Help! I just saw my boo's shadow in my bestfriend's photo

Hi Emeh,I just found out my best friend has been sleeping with my boo.Recently, she has been going on trips to the UK and it always coincides with when he travels.I didn't think much of it until she shared a picture on her Dp and unfortunately for her, she was wearing these electric blue shades which reflect.I zoomed in and to my shock, I saw my boo's shadow .I know you may say how do I know but this but this is my boo we are talking about .I have dated him for 2 years now .It's clear he took the photo in a hotel.
I called her immediately and she picked up.I then told her the photo was nice and asked who took it,she was so defensive and started forming no network in London.She then dropped the call and immediately changed the photo.
I called my boo and he didn't pick up.He called me later and I told him to send me a pic he said his battery was low.
This boy has never taken me on a date.Last year, to my shock,my friend who is from a poor home just said she has a UK visa and claimed it's a maga that did it for her.I have never seen the so-called maga.
I'm convinced my boo is the one funding her trips.Please what do I do?