Confused and Worried

So...after almost of tear of talking about another baby and loosing my father in law, I thought that my bf would be accepting of another baby...this whole time we were thinking of names and all the what if's, thinking he finally was ready...he is 1 of 10 btw...well on Friday I found out I was pregnant, of course I am estatic and believe my father in law gave him to us...but my bf not so much he's being distant, stand offish, and just plain ole selfish...now like I mentioned we have a 5 year old daughter, and before her we lost a baby that had anencephaly (a non formed brain and skull)...so with all this going on I'm afraid to loose another baby and I don't exactly understand why he's being this way...we've known each other for 12 years and been living with eachother for 7...I don't exactly have a support system in my family it's just really been the 3 of us and though I'm looking forward to 4...idk if I'll make it...so any insight or similar stories would be greatly appreciated...