I had been dating a girl for about 4 months and I never did this before or since, but I had a really bad day at work (toxic boss, etc...) and I went over to her apartment and after we hung out for a while I mentioned how I was feeling and said the reason I came over was to be around someone who was on my side. I didn't need any practical help, just some emotional support. This seemed to bother her and she said something to the effect of "I'm not your mother". This really bothered me and has since been in the back of my mind when I date new people. I'm able to meet and date women just fine, but I have this lingering fear that some day I will have a rough spot and they'll leave me.
I understand that there are reasonable limits to this and if you depend on anyone for too much emotional labor they'll eventually get sick of it. But my experience with this girl lead me to believe that any expression of weakness on the part of the man is inappropriate in a relationship.