No matter what you do, if she ends up with the other guy you will think whatever you did was wrong.
But it won’t be.
Because she will ultimately choose who her heart feels the passion towards.
If I were you, I would pull back some so she has room to see how she feels.
If you don’t give her room she is going to shut down towards you for sure.
You sound so hurt, and I am sorry.
I know it isn’t fair that you have worked so long and hard for her to see her with another.
Your work and patience will pay off though because we reap what we sow.
You will get her or better!
Try to stay busy and let her see that you are ok. In this way you are standing strong and will make you more attractive to her.
This other guy might not work out and could be a fleeting thing so hold your own and be strong!
Develop your strengths to fall back on and always know you are capable of finding great love.