after boot repair only windows start

after boot repair only windows start

I had Ubuntu installed alongside Windows 8. All was OK. Then i messed up
my Ubuntu installation and decided to reinstall it keeping my home
partition.
I reinstalled but as always Windows wasn't bootable from grub. I run
grub-repair directly from my Ubuntu installation and at the end it said
something about my boot files being too far from my system (Ubuntu). It
never said anything like that the previous times.
The next time I started the PC only Windows started without grub,
anything, directly.
I tried all: reinstalling Ubuntu twice, running boot repair, reinstalling
grub from the livecd but nothing: Windows always start.
Fast boot isn't enabled and I can correctly access the bios.
Here is my boot info from boot-repair http://paste.Ubuntu.com/6015718
The only thing I noticed is that /boot/efi seems to be empty while before
it was filled with boot files and I don't understand why.
I'm desperate.
What I can do?