me and my sweetheart have been together for 3 yrs...he has been seperated from his significant other for 6-7 years

Ok....me and my sweetheart have been together for 3 yrs...he has been seperated from his significant other for 6-7 years. She won't sign papers and he needs to stand by till his little girl is 14 for judge to run the show. His better half needs to get him for infidelity despite the fact that she was dating a fellow and lived with him for quite a long time and presently split. She proceeds to rest around and won't let any stay... appearantly she feels that it could look great on her part no man living with her...she had no water and hotness and children been remaining with us....now my bf needs to enlist a lawyer...his spouse claims she can converse with judge about kid uphold which I think she dont merit after the absolute of 18k through our the years he's given her and spends it on others and medications however her own children, she will not take them to school or pick them up....is it best for beau to employ a lawyer prior to petitioning for legal separation or feel free to record papers despite the fact that she needs to challenge? What is less expensive And best thing to do? This lady has made a great deal of passionate pain him and me and my little girl also with her methodologies and words. ALABAMA LAW HERE?