You'll both be fine. The first couple of days will be awful, but it will get easier. I also highly doubt that PPD will be triggered in this situation, but just keep track of your emotions. Remember that your baby will pick up on your emotions, so no freaking out in front of her!
She'll be fine with the bottle. It's very common for babies to resist taking a bottle when mommy (and her boobies) are around. If she's hungry, she will drink. Again, she may have a tough time the first couple of days, but drinking from a bottle is "easier" than BF, so be prepared for her to start resisting breast feeding. Don't take it personally- it's just easier for them to drink out of a bottle and they are self-centered little things!
As someone else mentioned, if you trust your sitter to drive the baby to you during the day, that is an option. It may be difficult if you are a teacher, but during your lunch and prep times it could work. Make sure you are pumping as often as you can and remember...
Your baby will be so excited to see you at the end of the day that you will be the MOST efficient person at your work just to get out of there on time each day!
Good luck!