Suzy41 - none of my business but...

Dear Suzy, you wrote about your husband's exwife "She's on depression meds and yes, it just the kids in the house with her. I have been there when she has refused an advocate or helper. She just wants it to be her and the kids, that's it."
Well, if she can't get out of bed for days, the depression meds aren't working. This isn't really a breast cancer problem, unless the cancer has gone to her brain (which is possible). It sounds like she's been wacky for awhile, which is her business, but not when it endangers children.
"Bill loses his patience, but she's threatened to take him back to court if he confronts her."
Divorce can be traumatizing for adults as well as children. Don't know what 'threat' she poses for your husband but a 'good father' puts his children's welfare above his own fears.
"Despite the way she is, he wants them to know how to behave when they grow up or they ever get a divorce and have kids."
This is the statement that really baffles me. Two teenagers and a nine-year old are held hostage by a depressed woman - what life lesson are they suppose to learn about divorce? Wackos get to call the shots?
"The kids do have counclars at their school."
Children are extremely protective of their parents. Do you honestly think they are going to complain about their mother to school counselors and risk being taken away from her?
"It just bothers me them being alone like that with her. She's always put pressure on H.18 ever since she was little. She does'nt think twice about it."
How do you justify leaving an immature 17 year old in charge of the welfare of a depressed cancer patient and two younger siblings? Either revise your opinion of the oldest child or get in there and help!
"Our hands a kinda tied. They live about 15 minutes away and we stop often a check on them."
Again, I have no idea what hold the ex has over your husband (did she get his cajones as part of the divorce settlement?). If you can't complain against her no matter what she does, will a neighbor or relative make a complaint to child services? Obviously, a woman who can't get out of bed, can't cook, clean or supervise children. If both parents abdicate responsibility, that means those kids are raising themselves. If you do nothing about it, don't complain about how they turn out. (Checking in on them periodically and then leaving them alone to fend for themselves? I'd be worried too!) Again, none of my business, I'm just a mom concerned about kids.