Dear Andypandy499

If you can get hold of Walking Meditation by Nguyen Anh-Huong & Thich Nhat Hanh (which includes a CD of guided practices) and practice before you go to the city it may help you cope with the gamut of emotions that that visit may trigger.

Are you going there for work?  Can avoid going to places in the city that have a strong association with your ex? Be aware when you are feeling nostalgic as this often ends up in suffering.  Eckhart Tolle gives an excellent talk on YouTube about he calls the pain body which may also be helpful in preparing for your trip.

kind regards Roberta