Oh I missed where he actually is going out with this new girl, not just talking to her. So he is not exclusive, he is pretty much dating her and lying to you about it.

It’s concerning that you actually see it as signs of him wanting to marry you and being madly in love with you. I see signs of him playing the field, keep meeting different women and not being serious.

I am concerned that you perceive it completely differently than pretty much anyone would. Hence I believe in therapy being helpful here