Saying that I have solved the issue is not quite right...but...here is what I ended up doing and how I have in a way attenuated the problem...
I decided to reset the phone, start it from new....really. I mean, not installing absolutelly anything at all and going step by step like it was the first time. By not installing anything I include the 5.1.1 release. Very important part of the process of getting my phone to work again.
Every app I wanted to keep, I simply downloaded it again (I actually erased purposely the back ups to make sure it wasnt an issue with a corrupt file). The same goes for adding music and libraries.
As for emails, which were, I beleive, the dataacessd issue that kept on reporting to apple on low memory...I simply decided to keep only the main accounts I have...and NOT SYNC IT WITH ICLOUD!!! I took special attention to blocking SPAM from being sent to the phone...since I was worried if maybe this could be a malware...(I have to say I am still in doubt if it isn't...)
I downloaded an app called Memory Free, which shows perfectly that my memory is still running at the edge...at the most it reaches 20 Mbs...instead of the 400 or 500 it is supposed to be, but the crashes are much less frequent now. I would say it only happens if I am multitasking against 3 or 4 apps at the same time.
I can listen to music again...and I can be multitasking again...I can write messages without the app closing on me...then again, I insist...APPS STILL CRASH, only not as often as before.
Apple absolutely doesn't reply...and certainly aren't even looking into getting this fix...the Genius at the store or over the phone...or whatever, arent aware of the issue at all (or they pretend not to be)....and insist this is a HW issue, which more and more it seems to me like a "HW design flaw" then an actual HW issue.
I have to say I am certainly falling out of love with Apple all together (iMac, Ipad, iCapsule...), since literally they are all falling apart with issues.