This is not intirely a bad idea. I had to the same to get over someone. It got to a point where I'm like "I have to cut her off". I never told her and just ignored, and while it was working something she did (she was looking for me very worriedly as to why I was ignoring her) made me like her again, though briefly, since when I saw her she acted like she wasn't doing worried about me. In the end we went our seperate ways and after some good time effectively got over her, so I was able to somewhat becomes friends. Now though, we seem to be having going on between us, though I may be looking to much into it AS USUAL, but we're in a good place. Not sure if the same will happen to you OP, but I might reccomend that you tell her to avoid that drama I went through because that left me utterly confused and delayed the getting-over-her process.
If you do tell her, then it's a good idea to tell her the pain she's causing you, as that is a good thing to get off your chest.
P.S. You can love again. It feels hopeless now, and that you may never be able to give your heart whole-heartedly, but you can love again. Just give it time.