Just because you're on a "break" doesn't mean someone gets to treat you like crap. A break usually means you are not contacting one another for a certain period of time OR not interacting like you are in a relationship for a set period time.

If someone treats you that poorly you may want to consider ending things with them. If she is going to take pictures of the flowers you sent her burning I would say she has some real issues she needs to work on before she can be in a healthy relationship, and you deserve a healthy relationship with someone.

However, the decision is yours to make. See how it goes over the two weeks. When she comes back see what her behavior is like. If you think you two are in a manageable place and you feel comfortable giving it another chance, great. But if not, perhaps you should either set up some serious boundaries or end the relationship.

Whatever you do, don't just give in if she is acting all sweet again. If this relationship is something you find you want to continue something has to change, or else you're just going to get right back into the same spot. When one person changes in a relationship the other person has to respond to it. If you make a positive, strong change to be a healthy individual and stick with it, she is going to respond in some way or another. She will let you know which, and you will know where to go from there.