I want to adopt my husband's child

My sister went through something similar with her ex-husband. Generally, the child has to be considered "abandoned" by the non-custodial parent before a step-parent can adopt without the parent's consent. It probably varies by state, but in California, the definition of abandoned is no-contact for at least a year. My sister just had to wait it out until her ex lost interest in visitation and stopped showing up (she knew he would eventually) and finally her husband was able to adopt. Her lawyer advised her to wait two years after visitation stopped (even though only one year was the minimum required) before filing paperwork. That way, if he showed up to fight the adoption in court, he would look even more deadbeatish (is that a word?) and have less of a chance of being able to prevent the adoption. He fought the adoption and lost. He not only didn't visit, he also never paid child support, so that may have helped my sister's case too.