Heartaches

I am having a difficult time lately with L. It seems we are ALWAYS fighting. He and I. I really think that our personalities clash, whereas R and I match. I understand R. I DO NOT understand L.
So I am feeling a lot of guilt. You know, the main emotion of motherhood.
I don't like constantly badgering him. But I have always (or at least I hope) been the type of mom to carry through with expectations. I don't like to be lenient with one child, and not the other. If I say to do something, it should be done.
Now, I'm no tyrant. It's not like I'm asking him to scrub the floors, or even clean the toilets. It's small stuff, like, get dressed, time for school, come for dinner, brush your teeth, well, you know the mantra. And the answer is (take your pick here) "In a minute" "I don't want to" "Why do I have to?" "Why isn't R?" and many others. Of course the answer to the last one, why isn't R, is usually that he's already done it, being the golden child that he is.
But it's not just that. It's also the whining, and the complaining. How do you get your kids to be grateful for what they have instead of always, wanting, wanting, wanting more? Here is a small example:
I made pancakes for breakfast the other day. Not a common occurance on a weekday, but I was feeling generous and energetic apparantly. L loves pancakes. I also put frozen blueberries in them, knowing that enjoys eating the frozen ones, and also has previously enjoyed the frozen pancakes (commercially made) with blueberries.
After sitting down, he complained about the blueberries. Then the syrup (we make him use a cheaper version since he uses too much), then something else, although I've blocked it memory fails me here.
Why couldn't he just be happy and excited that I had made him pancakes?
Another:
While out doing some shopping, L expressed that he wanted a Puffle (a stuffed toy). Disregarding the fact that we have only just had Christmas AND his birthday during which he received 4 different stuffies, I told him that maybe he could buy one with his own birthday money. That was ok with him, but he wanted to go NOW! No, we maybe will go on the weekend. And then the whining starts. "Why do I have to wait? I want to go now! So-and-so has one, I NEED one!"
"But L, you just four stuffies less than a month ago!"
"I don't care, I don't want them!" (not true).
Sigh. I guess he's too spoiled. But his brother is treated the same, if not he gets more, and he's not like this.
Now here's the part I'm struggling with the most. Most of the time, he won't let me give him any affection. He shrugs off hugs and kisses. He definitely won't initiate them. When he cries and I ask what's wrong, he won't tell me, or I have to ask a million times and beg. I guess I should stop doing that now that I see it here in writing. Just let him cry. But that's hard to watch. And the kicker is, last night he said he only loves Daddy. And it wasn't during a heated moment either. He was upset, yes, but it wasn't screamed out while I was punishing him or something.
DH says not to take it to heart. And I'm trying. But part of me is going, "You ungrateful little S.O.B! I carried you for nine months, expelled you without drugs from my womb, ripping myself in half during the process, and gave up my freedom, my body, my sleep, my money, even my health for you, and THIS is how you repay me??!!"
But that's what mothers do, right?
It's just really hard to like him lately. I love him, of course, but like? Hmmm, only when he's asleep!