My boyfriend doesn't say much to me. He used to talk a lot, but over the past four months, he barely responds to any of my questions. I think he's cheating on me.

I'm not sure how his inability to respond to your questions proves that he's cheating on you. Not all quiet men are cheating on their partners. Having said that, maybe he's just trying to find some space for himself. Give him time.

I moved to a new city for a job over a year and a half ago, where I met someone I really liked. He was kind, considerate and we got along really well. So, after a few months, we began living together. My job ended a month ago, after which I had to leave and move back to my hometown. I assumed my partner would want to move with me too, but he insisted on staying back, saying it would be impossible for him to move. He also said that I should be the one willing to stay back, for the sake of our relationship, which I thought was unfair. We have ended it, of course, but I sometimes wonder if I made a wrong decision. Should I have stayed?

Relationships are a lot about making compromises. You could have stayed, of course, but that would depend entirely on how badly you wanted your relationship  to work.

He could have moved too, if he wanted you in his life badly enough. The fact that neither of you chose to change or consider doing something for the other person only shows that neither of you was as committed to this relationship as you like to think you were. There's no point thinking about what could have been. I think it's best that you move on, and focus on how you did what was best for you at the time. I'm sure your partner feels the same way because, if he didn't, he would be at your doorstep by now.