So I'm only pumping 3 times a day but already have more than enough breastmilk. I want to keep it…

So I'm only pumping 3 times a day but already have more than enough breastmilk. I want to keep it fresh for her so I already had to freeze some of it after pumping because my fridge was still full. Any moms here who already have experience with defrosted milk ? Is it really still a good quality of milk, after you supposedly able to store it up to 6 months in the freezer ? 😮 maybe it's a silly question...I'm just wondering and only want to give her the best.