Hello I have recently had an experience with someone who we now believe is a psychopath...here is a link to a description of what a psychopath is in case you don't know

https://www.verywellmind.com/what-is-a-psychopath-5025217#toc-signs-of-a-psychopath

So she has been trying to become a Catholic but it has not worked for certain reasons 
Do we have a duty to tell the priest what we have discovered? I don't know how the church deals with this type of situation.
She also believes she does not need indulgences nor will she be going to purgatory...are these denying articles of the faith? And she believes if she becomes a Catholic and recieved the last rites she will go straight to heaven...which is presumption correct?
We no longer associate with her because of obvious reasons as well as veiled threats she made against our family. 
But I am concerned over her becoming a catholic with these issues.

My husband met her last year because she needed some help with her RV and no one could help her get it fixed...I do pray for her And really hope she can repent because it is definitely demonic...I am not sure though if it is a mortal sin because it is tied to mental/emotional issues.
Also something we pinpointed was each person we know who has psychopathic tendencies had some issues within their childhood linked to their parents.

Hello I have recently had an experience with someone who we now believe is a psychopath...here is a link to a description of what a psychopath is in case you don't know

https://www.verywellmind.com/what-is-a-psychopath-5025217#toc-signs-of-a-psychopath

So she has been trying to become a Catholic but it has not worked for certain reasons
Do we have a duty to tell the priest what we have discovered? I don't know how the church deals with this type of situation.
She also believes she does not need indulgences nor will she be going to purgatory...are these denying articles of the faith? And she believes if she becomes a Catholic and recieved the last rites she will go straight to heaven...which is presumption correct?
We no longer associate with her because of obvious reasons as well as veiled threats she made against our family.
But I am concerned over her becoming a catholic with these issues.

Yes, I would discuss your above concerns with the priest.  Let him decide if she should become Catholic.  The priest has years of special training to deal with people like this.  Of course, continue to pray for her.  I will say some prayers for her too.

Wow, after reading this now I’m wondering the difference between a psychopath and a narcissist

All psychopaths are narcissists.  Not all narcissists are psychopaths.  However, it might be closer to say that all narcissists are at least sociopaths.

So then I’m curious when would a narcissist go too far, cross that line and officially become a psychopath? When he commits his first real crime?

Psychopaths lack empathy.

Hello I have recently had an experience with someone who we now believe is a psychopath...here is a link to a description of what a psychopath is in case you don't know

https://www.verywellmind.com/what-is-a-psychopath-5025217#toc-signs-of-a-psychopath

So she has been trying to become a Catholic but it has not worked for certain reasons
Do we have a duty to tell the priest what we have discovered? I don't know how the church deals with this type of situation.
She also believes she does not need indulgences nor will she be going to purgatory...are these denying articles of the faith? And she believes if she becomes a Catholic and recieved the last rites she will go straight to heaven...which is presumption correct?
We no longer associate with her because of obvious reasons as well as veiled threats she made against our family.
But I am concerned over her becoming a catholic with these issues.

If you are not a religious and not related to this person then you should not say anything to her priest because whether or not her priest baptizes is none of your business.

If you are not a religious and not related to this person then you should not say anything to her priest because whether or not her priest baptizes is none of your business.

I would like to clear something up...my husband and i introduced her to this priest and recommended her per say as a woman who was interested in becoming catholic. We had many ties with her within the church and she even lived on our property twice to help her out, but now that we see/know this about her we feel it may be our duty because of what I stated above. 
I want her to be saved but i don't want her to come into the church as a pretender with our knowledge and that somehow be on our shoulders for not telling what we know.
Would it be any different if someone wanted to be baptized but did not repent of their adultery or alcoholism, etc and you knew but made no mention of it to anyone? Would that person be liable before God? That is our biggest concern...her habitual lying is very concerning.

This video helps explain the differences well, from a Catholic perspective:

I saw this several years ago and it was great! Very interesting topic and Ann’s perspective was truly enlightening. I don’t remember all of it and it was a very long video, I think 3 hours, so watching again would be difficult for now. But thank you for posting it is fitting for the topic