I think there are a few things which need to be taken into consideration when trying to weigh between personal factors and academic ones. Academically, you should try to avoid schools where there is only one person you are interested in. Their interests could change, your interests could change, they could be jerk, they could change schools, they could be awarded a 2 million euro grant to do research in Italy for the next five years, these things happen. While I think it's bad form to make plans assuming you are going to change your mind, it is important to have the flexibility if you do. Additionally, as wheatGrass pointed out, your career goals are important here, you have to live in this decision for the next 5-8 years, depending on the field; however, you have to live with this decision for the rest of your career. The way I look at is that as soon as the personal circumstances start negatively affecting the academic ones, then it is a problem. If you will be so unhappy that you will do worse work because of it, go where you will be happier.