Cheating on your partner?

i was in a gay relationship with my partner for 5 years, one day she came home and said she didnt know if she wanted to be in gay relationship anymore, wanted children etc. said there was noone else, she loved me, then she didnt know if she loved me in that way. found out she had snogged a male married colleague on a work trip and slept with him prior to our holiday, she is now with him, he has been married for 1yr, says his wife is controlling, etc etc. told my partner he would leave his wife for her, that he loved her, my partner said she thinks she loves him. i tried speaking to her, asked to reconsider and think of the 5 years we been together. (she was not out) i have had 2 random texts from her since then, but 2 weeks apart. its been 2 n half months now and its killing me. i never saw this coming, shes never been with a woman prior to me, only 2 blokes when she was in her early 20s, they both cheated on her!! can anyone help here?