All I can do is relate to you what I went through. I was tortured by my secret of love. While we were involved, I hid my feelings which was toxic to both my now ex-lover and wife but more toxic for me. I was out of control, and the emotional solitude was hurting me more than anyone.
Admitting it to myself was step one...it helps
Admitting it to my wife was step two...it helped a lot...
Admitting it to the person you love...was an incredible relief.
I was worried she would never talk to me, want to be with me...etc. Luckily I fell in love with an amazing woman who took it in stride. Our relationship had ended but our friendship has flourished. It didn't work out for me the way I would have liked but all in all, telling the person was an important step...
Good luck, its tough to do I know. We all fear consequences, but if you can't tell someone you love them without fear of them running away...would they be worth maintaining a relationship with anyways?