Some people have the Terrible Two's.
Other people have Lovebug Two's... and Terrible Three's.
The REASON the word 'terrible' is in there is for a very, very good reason. It's because they are crazy making terrible times that most of us survive by the skin of our teeth, and it lasts 6-12 months.
My very biased opinion (having had LB2s & Terrible Threes) is that 3's are harder. They're more verbal / cognitively advanced and OUR expectations are higher. Both our expectations on THEM (since we've already had a year of them learning, listening, being absolute sweethearts) and our expectations on ourselves (because, really, our parenting is NOT why we skipped the terrible 2's... it's a cognitive emotional stage of independence seeking and a MILESTONE... but already having had 2 solid years of "what worked" it's easy to get cocky. And then have that all come crashing down when they hit that developmental stage.)
My mum gave me this INVALUBLE piece of advice from raising all of us (very different personality kids):
The HARDER they push away, the faster they come running back. Revel in those, because you'll have a great day, or a great week, or even a great hour or two. It's *almost* as if they're testing you to see if you REALLY love them. Really? Even if I do THIS??? Then they push away again. True for EVERY independence seeking phase; toddlers, teens, new wives/husbands/mothers. You just ride through it, and cement the bond when they come running back, so you can make it through the pushing away phase.
And from neuropsychology:
Consistancy is reeeeally key with tantrums. The MOMENT you give in, you've just reset the bar on how long the NEXT (several dozen) will last. If you give in early, they will pitch fits ALL the time, for EVERYTHING, and whine/whine/whine. If you hold out, but give in in public places... they will pitch them in public places (and at home, and when guest are around, and, and, and but ALWAYS in public). If you hold out for 30/60/90 minutes... the next couple hundred tantrums Will. Last. That. Long. It's the theory of "random reward", and it works on kids and adults. We will TRY for that random reward FAR more than for a constant reward (think gambling, think the teacher that randomly throws out candy for a right answer. How many of us would pull a lever for $8 an hour. VERY boring job. Yet people will pull levers to LOSE money, because they MIGHT make $8 an hour. If a teacher ALWAYS hands out a consistant reward, students ignore it, by and large, it's normal/expected. If *randomly* a reward pops out JOY! and all of a sudden the teacher has a VERY intent classroom.). It is NOT CONSCIOUS. It is not a ploy. It's hardwired into our brains. Our brains are trying to find the "trick". NOT our minds. As adults, we know better, but our BRAINS are hardwired to search for patterns and exploit them. ((IT DOES NOT WORK IN REVERSE. RANDOM PUNISHMENTS = RANDOM REWARD ***FOR THE BAD BEHAVIOR***. Because sometimes they DON'T get punished for it, kids/adults are faaaaar more willing to do the bad behavior; think speeding... for the reward of NOT getting punished for it sometimes. Rather ironically, in the few towns that randomly send out $100 checks to drivers going the speed limit; in addition to fining $100 for speeding... nearly no one speeds. Because everyone wants to get "caught" going the speed limit. But in most places, where one gets a ticket if they get caught speeding, most people speed. Even if it's only "a few" miles over. Because the reward is there.))
My OWN 2cents: Never get emotionally invested in an argument with a child. For 1; it shows poor grace. They have no choice but to do what we say. We win. Automatically, no matter HOW much they get angry about it. For 2: it's like getting emotionally invested in an argument with a piece of furniture. We all do it from time to time, and it's usually regrettable / makes things a lot harder on US.