I think that expressing yourself is perfectly normal and healthy. It is letting people know how you feel, what you want, or what you need. I haven't met a real mind reader yet, and if I don't share these things in a relationship, then I have no right to expect that anyone will be able to know or understand.
Complaining is complicated. If it can't be resolved, but there are some emotions that need to be expressed, I'll let someone know that I am venting. For example, frustration over a computer crash. No one can replace what was lost, and no one is responsible, but sharing the frustration is healthy. I don't think complaining constantly is healthy. If I find myself in "complaint" mode, I need to seriously look at why I am feeling that way and deal with the underlying negativity or issue.
To me whining is just negative emotional manipulation. Getting someone to do something you want them to by making them "feel" bad. If I walk around and whine about how "tired" I am, then I leave a confusing message. If I am tired and let someone know that I am too tired to fix dinner, and would they please cook or pick something up, then I have expressed how I am feeling and what I need.
But honestly all of this is pretty new. It took me a long time to learn to say anything about me and a while to learn how to express it properly. Just because someone doesn't listen or agree doesn't mean that what I feel or said doesn't have any value. They may just not agree. If they are dismissive, then they are not worth my time or emotional investment. I guess at some point, I started to learn to validate my own feelings, needs, and wants, and that takes away the fear of expressing them or the need for others to validate them.
Just my .02.