I don't think Bono had problems on drugs. He may have tried at some point but it doesn't make a problem. If he had abused everyone would have notice... I mean, his vocals were affected by smoking cigars, just imagine what would happen sniffing cocaine or smoking harder pipes. I don't think he would ever shoot heroine... he hates what happened to his friends.
About being with other woman all the names he's been linked to have been denied by himself except one... Winona Ryder circa the Zoo TV era. But he didn't left Ali for Winona, it was they spent an intimate weekend together. Nevertheless that's gossip and I'll leave it to Oprah.
Adam was an alcoholic. He admits it. And Larry is the one who has helped him the most. Actually Larry sign in to record the Mission impossible Theme in order to take Adam to the US and make him forget his problems for a while. Ever since then Larry has stood fighting him, encouraging him, talking with him, but he always diguises his help under the Grumpy Mullen atitude.