Unexplainable2-3 second delays and lag for the past few days

I cant seem to find the cause of this, but it's driving me nuts. For the past few days now, i think it started as early as the 29th of May (with it being the 2nd of June now), i've been having an unexplainable lag and delay while playing FFXIV.

Every interaction with an object, for instance the Summoning Bell, or a Mining node (and the actual mining afterwards), or basicly any interaction with anything at all does not take place for me till 2-3 seconds later. This can be from opening or deleting a mail, throwing items away or sending them to my retainer, anything that requires an interaction with something.

It's making playing the game next to impossible for me. I can barely mine since clearing even a simple node takes 40-50 seconds (3 seconds before it actually starts striking at it, and then the usual recast time from the animation). I cant do any battles, tried to help out my FC and i managed to get hit by every attack the Hydra did on me. Ones that i wasnt even close to and that i always easily dodged in the past. Even Titan was giving me trouble despite just needing to stand still as the Tank :/ Siimply doing my 1-2-3 rotation had such massive delays that they barely grabbed the hate needed since they were spaced out a lot.

Before all this, i had perhaps a 100 ms delay, which was perfect to me. I never had a single problem playing this game, but now its impossible to play for me, and i have no idea how to fix it anymore. It's not so much physical lag, since my character moves as smoothly as he ever did, it's just the connection since to other people i appear to be warping around and there's the famous red connection icon next to my name most of the time.

I havent installed anything since (or recently before this happened) or changed any router settings, nor am i or anyone else in the house downloading (which would be inconsequential since i have a stellar ISP with nice speeds, but alas). All my drivers are up to date, and my windows install is less than two months old.

Lets see...

Server: Behemoth (NA)
Physical location: The Netherlands, Europe.
Internet Provider: Ziggo (already checked, no maintenance or problems reported)
Connection speed: 90.40 Mbps Download / 8.73 Mbps Upload

Windows: Windows 7 - 64 Bit
Processor: AMD Athlon(tm) II X4 620 Processor 2.60 GHz
RAM: 12,0 GB
NVIDIA GeForce GTX 460 (more than enough)

Any help or suggestions would be more than welcome

Slight update:

I ran a program that alters the use of your router, sending more packets towards it and thus in turn should make things more responsive.

It helped, a little, in the way that opposed to now getting a 2-3 second delay on every action/interaction, the speed is fine for 20 seconds, only to get a 2-3 second delay spike before it repeats itself.

Which by itself is more playable, but just far more anoying. Crafting Macro's skip lines because the animation hasnt triggered/finished yet for me while the timer keeps going after 4 actions go off perfectly, wrecking many crafts.

I have yet to actually find a "solution", just reduced the problem (or made it more anoying) by throwing more packets and requests out there.

Any help, suggestions or even experiences would be perfect and much appreciated.