I'll answer the question of when and how we like to use magic (and when and how not) by sharing my answer to one of our customer's questions.
Question from James:
Dear Twichery: Regarding your Reversing Oil, how would I use it? If someone has hurt me by not keeping promises and talking behind my back after I have given them a lot of help (which I regret) but I don't think the person has actually cursed me, can I use Reversing Oil or is there anything else that would work better? Will I get bad karma for using it? How can I protect myself?
Dear James: I wouldn't use Reversing Oil for this one, as it only works in reversing another person's spell. You are right in leaning toward self-protection rather than being aggressive. Personally I only ever use an aggressive magic on someone when they have already used an aggressive magic on me. Otherwise the karma is too strong against you because they did something non-magical, but you're doing something that IS magical. So I would continue toward that protection ideal by doing two things; one magical and the other not magical.
The first and magical solution is a Fiery Wall of Protection Oil because 1) it will act as a defense against that person's influence and 2) applying it will send a reminder to you that you are no longer allowing that person within your circle. You can also use an Uncrossing Oil, especially if you think the person is casting spells on you.
The second and non-magical solution is (ironically) even more powerful than the magical solution: Withdraw your trust and association from that person completely. Your no longer trusting them is actually WORSE than a curse because they lose any ability to associate with you. If your friendship is truly valuable, then losing it is a sufficient loss.
THE most important thing in this world is YOUR OWN SELF-RESPECT. A base level of civility and maybe a kind word is all anybody should ever get from you until they have demonstrated BY THEIR ACTIONS that they are worthy of your precious time and effort. (Unless it's something that costs you little, like holding a door open for someone.)
The only trick with this advice is that you will still feel hurt for a while because of your experience, and that wound will take time to heal. But you can console yourself in that you learned how to put your self-respect first.
I do recommend a Healing Oil (we do have that as well) for any emotional wound like this. Not only because it's a good source of magical help but because every time you put it on, it reminds you that YOU are number one in your life. And people who get blessed by your friendship are getting that blessing because they are likewise blessing you.
I hope this answer helps, my friend. Let me know if I can be of any further help or ideas.