I'm sorry for your loss. Try to be brave and as stoic as possible, I have to make a conscious decision right away that I am going to accept loss or I give in to my emotions and become a wreck.
If you live in your own home (or a parents) and you don't plan on moving for a long time have you considered burying her? My cat died in my arms and I thought about cremating her but I instead put her in the ground and planted a fruit tree so she's always right there. It's not any easier, but I feel better knowing she returned to the Earth and think about her when my Paw Paw fruit gets ripe. Plus the expense of the procedure and the fact you have to put yourself through it again when you pick up the ashes or they are sent. Just something to consider, hope I am not being insensitive, but pet crematoriums have no regulations and the cost to run the equipment means that pets are done en masse.
Consider a private little burial in your favorite park or on your property. If you have the money another option is that some places now will turn cremations into diamonds! It's expensive but how cool would that be?!
I'm really, really sorry for your suffering, hope my suggestions don't make you feel worse.