If you then try to speak any truth to the person, or to convince them that they're mistaken, or to offer insights or healing or to fix them, or to feed 'input' of any kind of greater truth to them, they will not be able to accept it.
Even though you are not really targeting the person - the self - but rather, the ego that they are associated with - the person still believes THEY are the ego. So any attempt to 'get rid of' the ego in them or to heal them or help in any way, will be experienced as you attacking them. And they will resist. Even if you have their best interests and highest good at heart and are just trying to help them to see the light, they will take it as an attack.
The ego can be quite vicious especially when it is confronted with truth in any form. And when the person is identified WITH the ego, they will experience it as though this truth is offensive to them. They will not want your 'help'. It's not that it's not helpful, but if the person can't separate out who they really ARE from the possessive, absorbing, blood-sucking parasite that the ego is, they're not going to be able or willing to listen. Then the person's reluctance to accept help, to seek help, to want help, or to get out of their own 'death wish', will be met with you feeling extremely frustrated in your efforts to 'save them'.
So this is what it really boils down to. We're not meant to be working on transforming the ego, or waking the ego up, or making the ego spiritual. We need to wake up FROM the ego. And that's very different. To wake up FROM the ego you HAVE to go through some kind of transition of identity. You have to transition away from believing in and associating with ego as your sense of 'self', leaving the ego's mind behind, and shifting your sense of self over to Holy Spirit's mind. It's a matter of pulling away from/detaching from the ego and realizing IT IS NOT WHO YOU ARE.
Same goes for the other person. They need to gain enough 'awareness' about the truth of who they are in order to not be LOST in believing that they are the ego. And if they are quite lost, it may take some time for them to 'wake up' from its possession of them, or rather, their doing-it-to-themself unconscious absorption into it.
So you have to be careful when you're trying to help others. Those with ears to listen with listen. But when they are too 'close' to the ego, you have to be extremely sensitive and careful about implying or making it seem like 'they' - the self - are the target of your offering of healing. If the self takes it to mean that you're trying to 'get rid of them', they will naturally resist, and that's totally understandable. No-one wants to be undone.
Love heals. But love is gentle and kind and patient.