He changed his mind

My bf and I started ttc several months ago and now he changed his mind about trying..When we first started talking I told him I was ready to settle down and have a family (he told me that he wanted that as well). He proposed and he brought up the starting ttc. he now just said he isn't ready for marriage (the would be second for both of us) and isn't ready for kids. I'm ready for kids. I tried for years with my ex husband with no success. I am not such what I should do...do i stay with the man I love very much and be unsure if I will ever have the family that I want so badly or leave to try for a child though adoption/ivf/or with someone else?