The humanity loss is regained per implant, sort of.
This information is on p101/102 of Chrome 2.
Note: The text there implies that the therapy needs to be done when the cyberware/implant is actually implanted, but this is obviously a GM decision (Not printing the full text for it as it's very large)
What the would-be-rehabed person needs to do is total up the amount of time they need to take for the things they want to talk about; this becomes (of course) very expensive.
4 Negligible = 1 Minor
2 Minor = 1 Major
2 Major = 1 Critical
Surgery Outpatient Inpatient/ICT
Negligible 2 weeks 1 week
Minor 6 weeks 3 weeks
Major 8 weeks 4 weeks
Critical 16 weeks 8 weeks
THERAPY COSTS & EFFECTS
Therapy Cost/Week Time Required HP Regained
Outpatient 1,000eb 14 hours/week 25%
Inpatient 5,000eb 168 hours/week 33%
ICT 10,000eb 168 hours/week 50%
So; let's say that Sven the Chromed wants to talk to his therapist about how the squishy human things he used to like are becoming more annoying.
Sven has two cybereyes and two cyberlegs, these are all critical surgery items so that makes 4 x 16 weeks of therapy outpatient, or 4 x 8 weeks of therapy inpatient. Sven also has a lot of other items as well, but he doesn't feel ready to talk about his Mr.Studd just yet to a therapist.
Sven opts to take outpatient treatment, so that's 64 weeks (1 year 3 months!) of talking about feelings and how lovely people are and how they are not just targets.
At the end of this Sven will have paid 64,000 eb and would have to spend 14 hours a week in therapy; he'll then get 25% of the HP loss back for the four things he's talking about.
Sven wonders if this will give him enough HP back for a borg conversion, oh dear Sven, oh dear.