In the examples I gave, the suffering *was* necessary.
Let's look at your examples and see if suffering could have been avoided with the same results:
1) Drug-addicted person going through detox. (If drugs weren't addictive, why would this example be pertinant at all?)
2) Sore muscles leading to muscle growth. (There's nothing logically contradictory about muscles attaining growth without ever being sore)
3) Emotional pain of adolescence. (This one's not very specific, but I may agree that sentient beings might inevitably be subject to things like unrequited love)
4) Childbearing pain (Again, nothing logically contradictory about giving birth without pain)
All physical suffering is preventable to an omnipotent being. If physical suffering is preventable but it's allowed anyway, that's pretty malevolent if you ask me. If there's a purpose for the suffering, then the person arguing there is a purpose has the onus of proof.