I think it’s ending

I’ve been with my partner for two and a half years and we have been engaged for two years. We have known each other for seven years and it just took us ages to get together. Now we are together I am beyond happy. I know he is my soulmate and he absolutely completes me. I am 27 and I have just went back to college with a view to going to University next year. The course will be pretty intense which would mean postponing having a family for 6/7 years. This would put me in my 30s and my partner in his 40s. I’ve started my course and my partner (who’s desperate to be a dad) said that he didn’t want to have children in his 40s and i think we might be splitting up. What do I do? I’m devastated. I want to lock myself in a room and never come out :(