Baby daddy

So i was with my sons father for about 5 years my son turns 4 next month we split up a little over a year ago he cheated on me with his boss and another co worker i was a stay at home mom so i know two wrongs don't make a right but i took him back and cheated on him we had a place together and we tried to make it work but it didn't we couldn't trust each other but he still let me live there for a couple of months now i had no family they lived in Arizona we lived in Rhode Island he ended up kicking me out when he got a girl who he worked with who he also cheated on me with any who he told me he would never take my child away from me ect ect we didn't involve the courts we just had him equally back and forth when i moved to Arizona now i have been with my man for almost 2 years and my bd kept telling me move back so we wouldn't have to keep spending so much money going back and forth Also so we could put him in school i had a good job out there and was planning to get my own apartment the cost of living out there is cheap and anyone who knows back at home in ri its not its expensive even for a shit box so i ended up moving in with my man and as soon as i told him i moved back he kept saying he was going to take me to court because he's the better fit now that i don't have a job again he used to be sweet now he's a fucking prick anywho he's been keeping him away from me wont let me see him for months i would hit him up every single day so i said you want to take me to court then i will show the judge that your keeping my son away from me for no reason and you never answer me when i ask to see him when i hit you up faithfully every single day sooo finally he's like oh i don't want to keep you away from your son blah blah blah but only lets me see him if I'm with his mother or his father like i need supervised visits mind you he worked a lot and was always out cheating so my son has never called him daddy he called him by his first name I'm the one who took care of him plus i worked under the table and every single dollar i have ever made has gone to my son even when he had him and i was in AZ and it was his turn i still sent money anything he needed he never did that with me he said when i have him you pay for him now he wants to act like I'm the bad parent and his parents are going along with it anyways now that i can finally see my son after MONTHS of not seeing or hearing from him and i only can see him when he's with his parents i don't complain so he doesn't try to keep him from me again but i try to make him let me have him for a couple of nights or even for the day now i have a job now and he's like i need some money for your son which i give him. Now I'm pregnant and his girlfriend is too and get this my due date is April 15th and hers is April 10th his girlfriend is a stupid bitch and tries to make it seem like i left my child on purpose when i had no choice and she tries to limit mines and my sons fathers communication i just fear that my son will never have that connection with my second child like he will with my bds 2nd child since he is always with him and wont let me take him and i cry because i feel like my son thinks i don't want him because he's always asking why i don't pick him up and why he doesn't come over my house and it just breaks my heart is there anything that i can do to get my son back also he says if he takes me to court then I'm only going to get weekends