Would be great to hear your thoughts on the below situation:

Her: 26y student, MBTI ISFJ, unclear relationship status
Me: 26y management consultant at a top3 Firm, MBTI INTJ, single, very shy (know it sounds funny but isn't)

History: went to school together, 10 yrs ago, had mild romantic interest in each other but never were real friends nor anything beyond, both ended up in different relationships

Now: by chance, we meet again after 10 yrs; exchange phone numbers; agree to meet; I invite her for dinner, we have great 3 hour conversation about our lives and future career plans and about her best girlfriend's relationship troubles; she invites me to go tobogganing together at some point, and to her birthday party; we hug intimately on leaving

She never mentioned a boyfriend at all.

Now at her birthday party, she mentions to me that she 'got to know someone' during this summer and will be spending some time with him in the next month. To her friends, she positioned this guy as her boyfriend.

I was surprised-to say the least-So I totally ignored the comment and talked about unrelated topics. On leaving, she was super nice to me, emphasizing that she wants to stay in touch with me, again intense hugging.

I don't get why she didn't mention a boyfriend earlier on before going out for dinner, or during it. She's certainly not playing double games and just after getting nice dinners.
I genuinely like her and would fight for her, but don't want to put her in a moral dilemma of deciding between two guys. I could get other girls but she'd be the best fit and I just feel she's the right person for me.

Thoughts? Advice? Options?
Thank you!!!