Breastfeeding is the biggie for me, too. I went back to work when dd#2 was about 4 mos. old, and coincidentally, a co-worker of mine was coming back about the same time, who's baby was about 5 mos. She weaned her ds before she came back. As she was telling me about it, I got such a knot in my stomach, I could hardly stand it. I realized then and there that no matter how hard it was (and at times it's really hard...), I was going to keep nursing/pumping as long as dd#2 wanted, because the idea of forcibly weaning her was just too abhorrant to me.
Co-sleeping is the other, and I have to admit, we are doing less of that this time--this kid just doesn't seem to need it as much. She sleeps through the night more often than our first daughter ever did at this age. If she does wake, we bring her in with us, but if she doesn't, we don't (although that is wreaking havoc with my milk production, so we may have to re-think the situation...)
FWIW, I don't think your bond is diminishing, so much as you are getting used to being back to work. Don't mistake the fact that you don't cry anymore for less of a bond.