First - long distance relationships CAN absolutely work if you are willing to put the time into making it work. A big part of that, I agree, is a solid foundation. The other is being willing to give your significant other your free time and being a good listener. My fiancee and I started on the west coast, I moved east, he stayed there. We spent the first 6 months of vet school apart, so that he could stay with his job and give them the time that he had promised, while I adjusted to the rigor of vet school. We used e-mail, phone, skype and snail mail to stay in touch as much as possible, and were sure to give each other time every night or every other night to listen to each other. There were days when it was really hard, but with a strong beginning, it can absolutely work. He now lives here with me and works full time.
In terms of prioritizing where to go - if you are committed to your partner, it's totally reasonable to choose a vet school location while factoring in whether or not your partner will be able to find work. Our priorities when deciding where to go were the program, the cost, the location itself, and the location in terms of where he could find work. We were accepted to a west coast, an east coast, a mid-country and an international school. When it came down to it, as much as we wanted to go abroad, we decided that given his field of expertise (conservation), it would be a bit more challenging to get work/visas there. He researched online what was available in each community/state and found that the location that provided the most options for him was the east coast. Luckily, I loved the program there so it made the decision that much easier. He moved to the east coast with me when the timing was right in terms of leaving his current job and acquiring a new one.
So, basically I would recommend that you both research available work opportunities in the areas that you are interested in (google, monster.com etc). Be sure he is willing to relocate/find new work. And if now's not the right timing for him to be moving, you could consider waiting until you are settled in while he searches from where she/he currently is. That way he/she still has a job/income and moves when they are ready and able financially.
Just know that it's all doable - choosing a location together, long distance or whatever permutation you come up with. It's completely what you make of it, how patient you are about whatever time is spent apart, and the strength of the relationship itself. It's 100% doable if you put in the effort. Feel free to PM me if you want to hear a little more and bounce ideas. 🙂