Surname ni baby

Hello everyone, I'm 6months pregnant. Need your thoughts about this I have a partner and we've been together for 7 years. He's a married man pero bago maging kami separated na sya for 8 years so Hindi ako Ang reason for their split. Si ex Kasi sugarol daw at di marunong magbudget (kwentong NG family ni bf ) now that I'm pregnant I'm worried tingin nyo ma carry Kaya ni baby Ang surname ni baby?