Hello.
As I understand things, you’re not to enter into a new relationship until after your previous marriage is annulled whether it’s (it = new relationship) overtly sexual or not. The sin of lust occurs first in the heart - physical sexual activity is just a symptom of that lust - just because there’s no sexual activity doesn’t mean there’s no lust.
It’s a sin for you to go to confession if you don’t have contrition - if you don’t intend to stop or amend your behavior, if you intend to continue with this relationship while you are already married in the eyes of the church. As I understand things, your confession would be invalid. The God I believe in can’t be fooled. Otherwise, I hope and pray you do go to confession and you’ll be welcomed with open arms.
Is your own salvation a priority for you?
My two cents.