Pregnant from brief relatonship
Last week, I found out I'm pregnant. The father is a grad student at my college. I'm a junior and should be graduating next year. We dated from December-April. I really liked him and think he's a genuinely great guy --- smart, responsible, kind. But we were just too different and drifted apart. In fact, we never really "broke up", we just started seeing each other less and less until we weren't seeing each other at all. He admitted to being preoccupied with school (working on his PHD) to fully commit to a relationship. I felt the same way, so we parted ways. We have seen each other a few times since then and usually wave/nod at each other.
Anyway, ever since I found out about my pregnancy, I've struggled with how to tell him. I'm still figuring out what I want to do. I don't know if I should let him know before or after I make my decision, or if I should even involve him in it. I actually ran into him on Thursday in the elevator. We had a polite conversation about finals, and then I burst into tears as soon as he got out. I honestly don't know how to tell him, and the fact that I see him so often is making me nervous. It feels wrong to walk by him so casually now, but at the same time I'm scared of his reaction too.
That being said, when and how should I tell him?