I haven't birthed on my own but I feel like you in that it wouldn't bother me if I had to. Don't get me wrong DH was great and supportive, but the 3 times I have been in labour I go into myself and just focus on the task ahead. With my last birth I actually spent the 30 mins in the shower on my own and he was born 10 mins later. So effectively did it on my own anyway.

I couldn't handle my Mum in the room with me, I think she would distract me and she has reached that age in life when she can get annoying. So yeah I would do it on my own if I had to and I wouldn't feel odd about it, although I can see how others might think I'm strange