do i have to continue paying alimony if my ex spouse in living with another man and now pregnant in the state of california

we have been divorced 18 months. She was awarded everything under the moon because the divorce went into default thru fault of my own. I was living in another state and was not familiar with the process and could not afford a lawyer. I make 5600 gross a month and she has 100% custody. I pay 1800 in child supoort, 400 for pre school and 1000 in alimony. I pay for all health, dental, and vision insurance and pay 380 a month in child support for another child. I make 150 a motnh when its all said and done. She moved and will not provide me her mailing address and I cannot see my kids. i cannot afford a lawyer and dont knowwhat to do