Tell me I'm not terrible

For considering letting my MIL keep my DDs overnight for the first time ever ? I have so much guilt but I REALLY think a complete night away would be wonderful for my dh and I and it wouldn't be terrible for the girls. My guilt comes from the fact that my 14 month old nurses through the night, ok not really nurses, more like latches for 5 seconds and then goes back to sleep, I or dh can get her back to sleep without nursing, it just takes longer. Would I be horrible for letting her go to Nonna's for the night? My 2.5 year old has also never spent a night away from me. I just feel so terrible for wanting a night away ?