"I left for personal reasons" makes it sound as if you're a difficult person to work on a team with and you can't work through personal differences with colleagues.
If I were in your position, I would leave out the fact that I left for personal reasons altogether. You do not want to say anything to a potential employer that could raise a red flag.
Instead, tell interviewers/recruiters that you left to look for new opportunities, as you didn't have the work/life balance to do so at said company. Let them know that you considered your options and you had the resources to leave your job and look for new opportunities. Even if you DON'T have lots of money saved up, you don't need to specify what type of 'resources' you were referring to. They will assume you mean money, but it doesn't matter. This will also give the recruiter the impression that you're not desperate.
I would avoid talking about any personal disputes/issues you had with other coworkers/employers as this will immediately send up red flags. Even if you mention difficult coworkers/employers anecdotally as evidence that you had good cause to leave you may still raise red flags.
Gloss over why you left and instead take charge of the conversation and tell them what type of company you WANT to work for. Describe to them your ideal work environment.
Heres a sample answer, that you can work with/edit until you have a strong answer.
Question: Why did you leave your previous company?
Answer: I was ready to look for new opportunities but did not have a great work life balance. When I was working I did not have the time to look for new opportunities, but I had the resources to resign and begin looking full time. I'm very interested in working for a company in the [XYZ] industry, and I'm also intent on finding a company that is inline with my values. I think customer appreciation is extremely important and I'm specifically looking for companies that actively seek ways to provide value to their clients.
