Congratulations on your admits! Amazing job with your applications, and Wow. Wednesday!
The bigger question is your partner/significant other. How do they feel? Do they think you should go to Stanford or Kellogg? I would base at least 50% of my decision on that, as long as they are being reasonable and not just trying to please you by telling you what they think you will want to hear (my wife does that for me and it always backfires, often comically so I always ask her over and over why she is making the decision that way when I suspect it benefits me more than her). In terms of your partner and you - BSchool changes a person substantially and chances are stacked against you. Business Schools work hard to shape new leaders and make a new person out of you. To do that, they have to break the old person and with that cut a lot of your old ways and life patterns off. You will be worlds apart when you graduate. Few distance relationships survive bschool - it is just the harsh reality. It is because bschools are so good at changing people.
In terms of VC, that is a VERY competitive field. I am afraid Kellogg does not come close to Stanford in terms of opportunities and connections. You can walk down the road from Stanford and find yourself in the VC capital of the world. Lots of Stanford Alums in VC and many of them are very accessible. This person has connected with a few Stanford Sloan alums even before matriculation and found them to be very helpful (
https://gmatclub.com/forum/insead-vs-st ... 45636.html) - you can also reach out to them and a few of the alums/current students to get a sense of career opportunities in VC after GSB.
In terms of money and scholarship, many people have given up full rides at Booth, Tuck, Kellogg to attend Harvard or Stanford. As you know neither S or H offer merit scholarships so it is almost always a full trade off and I see people often making it. I don't know if it is right or wrong and frankly, neither do those people or anyone else - nobody has lived 2 lives. The general feel is that if you are given a chance to be at the top, you should not trade it off for $100K. Obviously background and having or not having $100K influences a lot in making that decision but more often than not, i see people erring on the not taking the money side when it comes to HBS/Stanford. I feel a big part of it is the regret many people are afraid of.....
So back to reality.... In conclusion, I will go back to what I said first - if you want to be in Chicago/East Coast/Close to your partner, then Bay Area may not be the most ideal location in terms of how you fit your life and the scholarship makes Kellogg a more "right" choice too. It is kind of hard - it is relationship + $150K vs. a very hot degree with better prospects in VC. If you were looking for a change and get out of your current life, then GSB by all means. I am much less bullish on it in what I know about you.
Congratulations again and good luck with your decision!