Question on the Sidestep feat

OK, so from what I read, the sidestep feat states, that after an attack misses me, I can take a 5ft step as an Immediate action as long as I remain in that opponent's threatened area and it does not provoke an AoO.

Also the odd moving rule states, that the first move diagonally is 1 square and not 2.

Maybe I'm just getting hopeful that I found a good use for this feat, but my question is this:

If an enemy is right in front of me, (we'll say medium sized, as is my character) gets to attack me and has 3 attacks, if he misses the first, am I able to diagonally side step to the side of him (I'm still in his threatened range) and have him fore-go his other two attacks because I am no longer in front of him?

I can't really find anything in the rules that state an enemy can't keep attacking you if you move, but at the same time, haven't found any rules that say they can either.

No, so long as you're in the enemy's threatened range it can keep attacking you - there is no facing.

This begs the question. What good is Sidestep?...Except for moving so that you position you or an alley opposite into a flanking position IF by chance the opportunity exists...not...really...worth it.

if your opponent is large you can move next to him too.

if you are next to a large oppoenent, 5ft step back so you can withrdraw the next round without provoking

you can charge an opponent, smack him, and when he tries to attack you move sideways so that your next ally can also charge him

move so that you can provide flank

move so that you move OUT of flank

the uses are kinda limited because it robs you of the 5ft step in the next turn, but they are there, not a great feat, but not a complete trash imo

Other possible uses:

Moving behind cover or partial cover

Moving out of a square that was made dangerous during someone else's turn.

Moving to be able to take attacks of opportunity on certain other enemies (prone enemies, spellcasters that are about to run away from the melee, etc.)

Moving to avoid full attacks from other enemies

Setting up teamwork feats