Writing an email to politely decline a job offer

Hi Brent,

I will not accept your job offer.I got another job offer almost at the same time, and it was really hard for me to decide. I decided to accept the other job offer. I recently got over a mental stress, and that job will be better suitable for me since it is in a slower-pace university lab and it's right in my city where I can stay close to my relatives.
I was so nice to talk to you and learn about your technology. I hope to be able to reconnect with you in the future when I feel more ready.

Again, thank you so much for giving me such a wonderful opportunity. I hope you will find the best candidate and I have no doubt your company will strive.

Best,

Xuemei.