I am 30 and have an 11-year-old daughter, Rose. I am dating a man 24 years older than me — Peter — who has a 14-year-old son, Jason. We all live together, with an au pair. Peter is a successful businessman who looks after me financially. I work part-time, so he pays for my daughter to go to public school. I have been living with Peter for a year, after an eight-year relationship with my ex-boyfriend, Simon. He and Rose were very close and Rose still misses him a lot.

But her behaviour is changing and our relationship is deteriorating because of Peter and Jason. Peter buys him expensive gadgets, mobile phones . . . things that most adults only dream of. He doesn’t let Jason move a finger — the boy will sit watching TV while Peter washes the car. Jason is very disrespectful to his father, often referring to him as an a***hole or idiot, and will shout at him in public. Jason has got blind drunk and thrown up a couple of times while we were out. But nothing seems to bother Peter. He doesn’t even raise his voice.

My style of parenting is entirely different. Rose has to earn things she wants, do her homework, keep her room tidy and be polite. If she is naughty she gets punished — banned from the computer or TV. I have managed to keep my head out of Peter and Jason’s business for two years. But Rose is starting to question why she gets told off and punished when Jason can do what he likes and use bad language. She is starting to detest me and pay less attention to what I say. I’ve tried to talk to Peter but if he says anything to Jason, Jason threatens to go and live with his mum. Peter is too afraid to lose him, so he complies.

Friends tell me that I have a nice home, a good school for Rose and all the worldly goods a girl could have, so I should enjoy it and ignore Jason’s behaviour. Am I being crazy wanting to throw away a good life? Am I being melodramatic, since all families have problems? Should I persevere?

A part of me says that money is not everything and I will manage without Peter, but I don’t want my daughter to grow up thinking that I favoured Peter (or Jason) when she needed support. Rose has said she would like us to move out: I could still carry on dating Peter if I wanted, but she doesn’t want to live with Jason. It’s the first time in my life I can’t decide on the right thing to do.
Louisa

You say that “all families have problems”, but let’s go to the crux of this: the trouble is that you are not a family. You are four characters in search of a structure, and unless somebody takes charge soon, the little you have will fall apart. Maybe that would be a good thing, but I see no reason to be so negative. It could be that you all come through and manage to construct your own version of family life. Now that you are 30, this is as good a time as ever to put yourself to the test — stepping back to see whether you are, in fact, mature enough to see just how much work needs to be done beyond your relatively simple either/or.

I want to consider each of you in turn, starting with the youngest. Rose was born when you were 19, and not so long after that you provided a loving father figure in the shape of your ex. Examining the timescale, I’m guessing that you began your relationship with Peter while still with Simon, in which case Rose would have been exposed to tension and pain. Now, understandably, she misses the only father figure she has ever known, and has been thrust into a difficult new set of relationships with little preparation. She has to share you with two strangers in a household where your own role is passive (more of that later) and where she feels a Cinderella. No wonder she wants you to herself, and you’re absolutely right to recognise the urgency of addressing her needs.

From your description Jason sounds pretty obnoxious, but this is a 14-year-old boy who has endured his own loss (his parents’ marriage) and is desperately seeking attention, which Dad provides by means of his charge card and minimum involvement. It’s interesting that Jason threatens to pack his bags and live with Mum whenever his father tries to discipline him. I’m wondering why the mother didn’t get custody in the first place. There is another story there; I worry that deep down this troubled adolescent may feel unwanted by her, adding to his woes. You have come into his life quite suddenly, and he is probably confused by your sexuality — I bet you are a very attractive woman, and after all, nearer to his age than to his father’s. Have you thought of that? You’re not being a mother figure, nor even filling that trickiest of roles, the stepmother figure — and I ask you to be honest with yourself about how hard you have tried to be his friend. Jason’s needs are as acute as Rose’s.

To skip a generation to Peter — this is a man who is doing his best as he sees it, but not providing effective fathering for his son. He is the old-fashioned provider who thinks that loving and writing cheques are synonymous. Weak and probably suppressing guilt, he fails to see how much Jason needs parameters as well as reassurance; he ignores your daughter’s evident unhappiness (otherwise he would listen to you); and he totally fails to treat you as an equal partner. I hate to say it, but his role in your life is that of the Sugar Daddy and I wonder whether it makes him happy to enjoy the gratitude of the young woman he is sharing his life with, but who knows she could “manage” without him.

Be honest: didn’t you ditch Simon and move in with Peter partly because of the quality of life that your friends so admire? I don’t blame you: all of us want security and if that’s with a touch of luxury, so much the better. But to your credit you’re now seeing the limitations of designer clothes and school fees, when so much else is not right. Your letter contains the beginning of self-know- ledge: the first step on the road to adulthood. Does that sound harsh? Well, look at the second sentence. Revealingly, you use the word “dating” to describe your domestic relationship with a man old enough to be your father — implying a youthful transience which, if it informs your feelings and behaviour, will work against this developing into a real partnership. It’s time to stop always viewing yourself as somebody’s girlfriend.

Before you can decide what to do you must ask yourself some searching questions. If Peter’s business fell about his ears and he was desperate, would you stay with him and support him with affection and strength? He looks after you financially, but do you look after him emotionally? Can you learn that “bad” Jason is just as important as “good” Rose in this whole equation, and that you need to try to know him? That blaming Peter and Jason for Rose’s unhappiness won’t do? That your strict mother strategies could be as limited as Peter’s weakness with Jason? That it doesn’t work pretending that the Peter and Jason relationship isn’t your business, while resenting it? You need to answer honestly. Then you and Peter have to start talking properly to address the issues that your instant cohabitation has exacerbated — that is, the deep unhappiness of both children. You must lay down rules of conduct that the two families obey, with absolutely no inequality in the way that Rose and Jason are treated. If you are to go on living there, you need to spend time with Jason on your own, and Peter must attempt to help Rose through her loss of your ex, Simon. Both of you have to realise that sharing a roof and an au pair won’t make a family, but tolerance, understanding, time, affection, respect and sacrifice are all required if you truly wish to progress to the next stage, and help each other to become a whole.

E-mail your problems to: bel.mooney@thetimes.co.uk or write to her at: times2, 1 Pennington Street, London E98 1TT. Detail such as your age is helpful. Please include your real name, but we will use your chosen pseudonym if you wish.

Bel Mooney reads all letters but regrets she cannot enter into personal correspondence.