This is beyond fucked up

So over a year ago my partner had to go back to his home Nigeria because his parents told him to and he went because he was financially dependent on them and still in their care, anyway it was because I was pregnant they were pissed off and angry he was at uni at the time and they paid for his degree he was an international student , however he does have two passports as he’s biracial, long story short he missed the birth and didn’t meet our child till she was 3 weeks old it took me months to get over that I finally felt like life was good for us until now , I’m pregnant again first baby is 15 months and he told his parents his mom has booked him a ticket back to Nigeria and he’s going for the year this is his decision. He’s going along with it, he will leave me when I’m 6 months pregnant and will miss 8 months of his babies life .. I’m shocked that this is his decision , I can’t get my head around it we’ve been together 4 years and he’s 23 , I’m 24 , I’ve ended it with him as he’s choosing to go on his own free will , the reason why he’s going is for nysc in Nigeria which u can do anytime before 30 , I don’t feel it’s necessary for him to go right now , I know I’m going to struggle but I can’t get my head around the fact he’s choosing to leave us now and quit his job , how will I cope on my own with a 2 year old and newborn , he has a really good job in which he just got a promotion in software engineering , and he’s giving it all up and going , this is probably a cultural thing too as I can’t get my head around it all but all I know is he’s leaving me yet again when I need him the most , two births he will miss out on.. I don’t even want to speak to him right now