What should i do? i cant get over her?

4 months ago my wife left from a 9 year relationship, 2 weeks after she left she moved in with another man. i left her alone but then 2 months after she came to my house and asked to take me to lunch, but then it led into her coming over for a few days while her boyfriend was at work cause she wanted to make love. she said she wanted us to be together again someday and wrote a letter expressing her feelings. i took a trip to california for 3 weeks and after i got to california she called and told me that she told her new boyfriend that she had cheated on him with me, and said she never wanted to talk to me or get back with me. i was crushed again cause i thought i was getting my family back. but then she called again and said she missed me and that someday if it was ment to be then our paths will cross again, im so freakin confused on what to do. we have two kids together and the kids took it ruff, i mean there mom and dad is together then 2 weeks later she has them for the weekend with her new boyfriend. they cry to me all the time wondering why we are not together, and my oldest is giving the new guy a very hard time. the relationship was rocky, we went through alot together but always stood behind each other. she calls and complains to me somtimes about the guy, and i try to help by giving advice even tho i hate that she did this to me. and alot of times when she calls she is just very rude to me. what do i do? why would she just move in with another guy so quick and put the kids through heartacke like that. i want to move on but after 4 months i still miss her so badly and dont know what to do. i asked for us to get back together and she just gets mad. and why would she snitch on herself to her new boyfriend about her being with me? is she gone for good or is there a chance on me getting my family back together. i pray everynight on what to do and even ask for him to help me move on, but all i ever feel is to fight to get her back someday. im lost, sad and miss my wife, so any advice would be great on the situation. thanks for all the advice in advance