Como dizer "meio da conversa" em inglês

Yesterday I was talking with a friend that I made on internet, he is like a e-pal. And I had to share my computer with my mom and I got off on msn. But me and my friend were still talking and I had to say goodbye very quickly.
Today I will say sorry to him but I need some help with these words.
How can I say:
"meio da conversa" (Ex: tive que sair no meio da conversa, papo).
"sair de repente' (Ex: não era minha intenção sair de repente).