oh dd always slept between me and the edge of the bed (with a bedguard obv)
There is some research to show that fathers don't have the same non-squashing instincts as nursing mothers - their sleep patterns are different or something - so I kept her well away from DH.
I really don't think your boob could suffocate a baby - they really do 'drop off' of their own accord when they are deeply asleep, it's not like a dummy that stays in. And if they want to stay on (and hence are not deeply asleep), then if their nose gets blocked they shuffle till they are clear, and usually you wake up and move as well.
Between 3 and 6m they are usually still feeding a lot at night, which is the time when cosleeping is the most useful as at least you can doze while feeding.
The classic 4m growth spurt is a time when many people who hadn't previously coslept start, just to get some rest!
After 6m when (theoretically) they are more active during the day and beginning to think about solids, you might find they sleep better so moving them would be less of a big deal. Remember that FSIDS recommends that you keep them in you room for the first 6m though.
And no-one's belittling your job, floatyjo, I think we were just at your reaction.