that's really sad :(
May Allah grant your phupoo a high place in jannah. The best thing you can do for yourself is to pray for her everyday. That will also bring peace in your mind and heart. Then, you need to overcome your emotions because think of it this way, even your aunt wouldn't have wanted you to stop your life, right?
Exactly what I was gonna say. Ameen.
Every time you feel like crying read Quran for her, do any good deed or give sadqa under her name. She'll be getting sawab for that & that is what she needs more than her niece crying for her. Praying in any form helps a lot to cope with sadness.