Just to clarify on the guilt, which I attached to the "libido" build up in projective identification, the sense of the reparation in the person having to call her friend has another dimension.
A patient with altruistic guilt after his mother died was related to his resentment. An altruist wants to merge and be close, give gifts, and more generally energy to the other person. Because this patient had resentments towards his mother, he didn't talk to her much and held back his "energy". When she went on to die, I didn't detect death wishes against her so much as the feeling that having inhibited his being close to her, meant that she could have been sad and "given up" in a way. The idea was that if he had been close she might not have gone that way. This is a variation of the omnipotence of wishes that the altruist's love can be magical and help someone, and to withhold this makes them responsible.
The link to the built up libido, that isn't projected into the other in PI, is probably better conceived of analogously to the narcissist's rage and aggression, or exhibition wanting to come out. The echoist, in PI with death, feels empty, dead, etc. and the built up libido can be expressed in things like cutting and various forms of pain that amount to "better to feel pain, or torture" than nothing at all (or be alone). I encountered this first through Wurmser and it has showed itself to be true in several patients. Cutting, being with someone dominating, etc. is an expression. However, this has to be differentiated from deutero expressions in PI with the castrated mother who is the model of being aggressed by someone else.