I'll try and keep this as brief as possible. After little contact with my ex for about 16 months, I am gearing up for the fact that I will be seeing him at a mutual friends birthday with his gf, sister and mum! We didn't end on great terms, but we were best friends, became more and then he told me that he wasn't ready for a relationship. 4 weeks later, he was sleeping with someone else and then when that didn't work out he started seeing someone else and moved in with her after 6 weeks. I had left the country by then but now I am back. A year later they are still together, whereas I had to take my time in getting over it all and moving on, and though I have dated, I have yet to find anyone serious. I'm just a little worried about it all, worried to see him, the gf, the interaction between him, his girlfriend and all his family. I feel I am over it, but then something happens and I am sent right back to a place of hurt and insecurity, especially as he is the one in the long term relationship and I am not. Any advice about how to get through the night would be very much appreciated, should I make initial contact or just try and avoid the situation as much as possible.