Our resident relationship counsellor

My sister-in-law gave us a houseplant for our anniversary and now visits it. She rings ahead, asks how it is doing, then comes round on a Sunday and stands over it with a little moisture meter she bought specially. Last week she said the plant seemed tense and looked directly at me when she said it. I am now watering a plant I did not choose on a schedule I did not agree to, in my own front room, and I have started feeling tense myself.

You have misunderstood the nature of the object in your living room. That is not a plant, monsieur, that is an outpost. She has placed a listening station in your home and disguised it as a gift, which is the oldest manoeuvre there is, and frankly a well executed one. I once worked for three months on a set where a single yucca stood between two people who could not be in a room together, and I can tell you the yucca won. So you must become the plant's primary carer. Learn its name in Latin. Speak of its soil with tenderness, speak of its light with authority, and when she arrives with her little meter, hand her a cup of tea and tell her the readings have been excellent since you took over. She will lose interest in a fortnight, because what she wants is not the plant, it is the Sunday. Give her the plant and keep the Sunday.

A chap I barely know from the allotments has started copying my shed. First it was the colour, which I accepted, then the guttering, then last month he put up the exact same little weathervane and waved at me while he was doing it. I have been building that shed up for eleven years and it is the only thing I have ever finished. Now people come down the path and cannot tell whose is whose, and I have caught myself lying awake planning a conservatory.

This man is not copying your shed. This man is courting you, and doing it badly, in the only language he has. A person who matches your guttering is asking to be your friend, but he has no vocabulary for it, so he has gone and bought a weathervane instead, which is a cry for help in galvanised steel. I have known this kind of devotion, in a career where a man once rebuilt an entire set because he admired how I stood in it. Do not build the conservatory, it will escalate and you will both end up with koi. Instead, walk down the path on a Saturday, admire his guttering out loud, and ask him for a cup of tea in his shed. Within the hour you will have an ally, and within the year you will have two sheds that match on purpose, which the French call a terrace and the English call nothing at all.

My father-in-law has moved in with us for what was described as a fortnight and is now in its fifth month. He has reorganised our kitchen cupboards according to a system he will not explain, and he has started answering our landline with the words 'the house'. Last week he put a laminated sign on the fridge asking us to let him know by Tuesday if we intend to eat anything on Thursday. I do not know how to raise this without starting a war that will be discussed at Christmas for the rest of my life.

You have made the classic error of the English, which is to treat a man's laminator as his personality rather than his cry. He has built a system because a system is the only room in your house that belongs to him. In my former profession, which demanded precise scheduling and a great deal of patience from everyone involved, I learned that a man who insists on knowing Thursday's arrangements on Tuesday is simply a man who wants to be certain he is still invited. So invite him. Give him one cupboard, one night of the week, and one genuine responsibility that he can do badly without comment. Then, and only then, remove the sign from the fridge yourself, in front of him, and say nothing at all. He will sulk for nine days and then he will be the best friend you have ever had.