Frozen milk help!!

So my fresh and refrigerated milk taste wonderful, close to sweetened almond milk. I pulled out a frozen bag and as it has a heavy lipase scent I wanted to taste it first before I let her drink it. It tasted so bad I gagged! I absolutely do not want to give her milk that tastes so bad. I have months worth of frozen milk! Why does it taste so bad? It's been in a regular freezer less than 6 months and was moved to a deep freezer. I just can't bring myself to give her this milk when my fresh tastes so nice. Have you all actually tasted the difference between your fresh and frozen? Is there something going wrong here? I don't even want to donate it it tastes so bad compared to my fresh. Help!