You are saying narcissist ex. If he is your ex he is not cheating on you and why would you care if he is your ex.
Forget about this and move on with your life. If you think that this is cheating on you - better think again and also know that this will go on and on.
Nope. Parents come with girls until they move out. Be a charming gentleman, and everything will work out just fine. Start by never calling her mom a narcissist again.
Start looking for a new job.
First, figure out whether your boyfriend is spending time with another girl. Then proceed to give warning to that girl if warnings to your boyfriend don't seem to work.
Leave, then empty the bank.
That isn't the correct way to deal with a cheating partner. If you know your partner is cheating, and if you still want to make it work than you should probably separate for a for a while, but inform your partner that you still want this relationship to grow. Also you should ask the cheating partner is they want to make something out of the relationship. That is my best advice. Or see a therapist.
No contact is the best way to part ways with a narcissist. You must remain consistent and end contact completely and forever.
Signs that she's cheating at work may be lots of late nights
One of most sensitive matters at work is when you catch your boss cheating. This is especially tricky when that boss is the highest person in the organization.
http://narcissismcured.com/Narcissism_Cured.html
The question is help them how? Refer them to counseling, but they don't want to be fixed, though you may want to fix them to be a 'normal' person so you can keep a relationship with them. If you are a lay person and in a relationship with a narcissist, you cannot help them. Just by the nature of your relationship and the pathology of a narcissist, things will get ugly, it will be at your expense and there will be no change in the narcissist. A good therapist will be the one to help a narcissist, but it takes a great deal of work on the part of the narcissist, a commitment to healing, only they don't see themselves as 'broken' or anything wrong with them, so an honest introspective communication with a therapist is rare. It's so hard to understand. Leaving them is best for you though and isn't that sad that that is also the way to help a narcissist, because they are sucking your goodness from you and using it to buoy themselves. So sad.
Get a police order of protection
That it didn't work out. The rest is none of their business.