Navigating the emotions of a 4-year old

So I'll admit that I'm starting to struggle. I've been in this mothering game for about 4.5 years now and it never ceases to amaze me how hard it is. My patience and understanding levels are starting to wear thin and I've still got at least 16 years to go until Baby Boy is 18.

My most recent dilemma is dealing with the attitude of my four year old daughter. The sass has started and I'm struggling with how teach her good manners. A lot of my lack of patience comes from being tired and disconnected. I'm trying very hard to reacquaint myself with what a good stay at home mother should be doing.....getting down on the floor more to colour, play games, etc. But I seem to constantly be butting heads with this moody and rude child that has appeared. Many a day is spent dealing with disciplining Baby Girl on how she should be talking to her mother and dealing with the hysterics that ensue when the consequences are enforced.

To paint a more clear picture - I speak firmly, she doesn't listen, I tell her to go to her room, she yells "no", I pick her up, she writhes out of my arms, I place her in her room, she spends the next 1/2 hour screaming at me. Not a pleasant experience.

What I do find interesting is the dialogue that happens after she has settled down. We seem to spend a period of time talking about how she is still mad or upset, but at least we're on speaking terms. The good thing is that usually later in the day she snuggles up to me and tells me she is sorry for whatever it is that she had done.

It makes me fearful for the ride to come. It is really hard not to take her outbursts personally. This is a strong willed little girl, who is going to push me to my limits and it's hard to know whether I'm picking the right path of teaching. I don't want to even think about what my already moody 2-year old son will be like in a couple of years.