cutody and support..pls help

[tgastte]

I filed for a divorced last May '08..here is the scenario; she left in jan 06 and left the kids with me they're 13 and 11 right now, so i moved out of the house aith the kids, put them to school, sports, and took care of their needs, basically i was the mom and the dad at the same time..kids did good with me since then, while she partied, got drunk and got caught in april 07 with methampethamine, charged with possession,under the influence and parapenalia...

she started sleeping around jumping from place to place and never call or visited the kids..or maybe she does whenever is convenient for her, the last time she saw our kids was sept 08..now she had a new baby from another man, lives in a studio apartment and the'yre claiming that they dont both dont have a job...now here is the most shocking part!!!! we went to court, mediation for the custody and being a nice guy i agreed to 50-50 custody and even drop the child support that she owed me which is $19,000 so we can just both move on..

our agreement is i will have the kids on M-F during school days and she will have them whenever she feels like it..she filed for OSC, went to court, since she doesnt have a job and we split 50-50 now the court slap me and had me paying $854 a month for child supprt...and its rediculous!! so i filed for another OSC for to modify support, im fighting full custody now since i had them for 4 straight years and took care of them, she didnt enforce the temporary suport yet coz she hasnt seen the kids and my kids doesnt even wanna be or see her at all...

now my question is can my kids be heard by the mediator or the judge for their custodial preferences?? what are my chance on this case coz my mediation is going to be on sept 09 and my OSC hearing is on sept 29 at rancho cucamonga court...im not going to agree on anything she say now i want ny back child suport and 100% custody since i took car of my kids and its detrimental fro them to move, coz i think she also want 100%custody....PLSSSSSSSSSS HELP!!!!!!!!