Katie’s fun, quite attractive and easy company. I met her a year ago on a night out and it was clear that she was really interested in me, so I suggested that we meet up again.

I probably wouldn’t have asked her out if I’d known how much older she is than me – I’m 27 and she’s 39 and very keen to settle down – but within a couple of dates I knew exactly what her connections were, and that changed my mind.

Her father is extremely wealthy and his darling daughters are the main beneficiaries. Katie has her own luxury flat, no mortgage, a substantial trust fund and a clothes shop, which is like an extension of her own wardrobe and full of designer gear. She works when she feels like it, which really just means popping into the shop a few times a week and chatting to her manager there. The rest of her time is spent looking after herself – going to the gym, getting her hair or nails done and shopping with friends.

When Katie described her car as a “little grey thing” and then picked me up for a night out in a silver Porsche, I really started paying attention and realised that, while she tends to go for an understated look in clothes and jewellery, everything is the best quality and price is simply never a consideration.

It didn’t take me long to realise that life is completely different with a wealthy and generous partner. All my previous girlfriends worked and I have a reasonably good job as a sales manager, but there were always those few days at the end of the month when we couldn’t afford to go out or had to juggle the bills.

Katie has had the sort of life that most of us can only dream about. She’s quite desperate to settle down and feels that time is running out to have a family, so it’s almost a question of whether or not this seems like a reasonable deal, in a way.

I pay for nights out but sometimes I wonder if that’s just an investment in a very comfortable future. If Katie and I got married, her parents would buy us a big house as a wedding present and any kids we have would go to private school – paid for by her dad – and have a great start to life. For Christmas, Katie’s main present to me was a skiing holiday in a luxury hotel in Courchevel, which cost more than £20,000. Her other presents were ski gear (not just clothes but skis), a signed first-edition of my favourite Harry Potter book and a Cartier watch.

Last year, she took me to New York for a long weekend for my birthday and she’s already talking about going to St Lucia for a summer holiday next year. I’m starting to get used to this sort of lifestyle and I don’t want to do without it. This sounds truly awful, but when her parents die Katie and her sister Susan will get the lot, and it really is a lot. Katie keeps bringing the conversation round to marriage and I am very tempted, especially when she suggested that I could change jobs. Her idea of the perfect honeymoon would be spending three months going round the world and when I said that I would never be able to take that much leave she suggested taking a break from work for a while and thinking about getting into something I really enjoyed.

It is the thought of swapping jobs and being able to do what I really want, without worrying about the money, that is the greatest temptation to me.

Recently I went out for a drink with Richard, Katie’s brother-in-law. He works in finance, but as Grandpa pays all the private school bills and Susan has her trust fund income, his wages are like pocket money. While we were out we bumped into one of Richard’s colleagues and the two of them obviously got on brilliantly. She’s a stunning woman with a great personality and after she left, Richard got pissed and told me that she’s the biggest regret in his life, because he never imagined that he would meet someone like that. This girl is everything he ever wanted, but there’s no way he would rock the safe boat he’s in.

And for the moment, that’s what is stopping me proposing, because meeting that girl made me realise that Katie is a bit dull. I wouldn’t miss her but I’d miss all the things we do and the life she’s shown me. The sex is OK but not brilliant and my porn habit is already increasing, which is a bit depressing after just a year together. She looks good for her age but, although she’s nice and safe, she’s a little colourless. If she wasn’t so wealthy the idea of marrying her wouldn’t have crossed my mind, but she’s also the ticket to a fantastic lifestyle.

I know this all makes me sound like a bastard but it’s not that simple. When I meet other women who appear to be great fun or really lively it makes me wonder what I’m missing, but if I give up Katie to pursue some mystery women and it doesn’t work out, what’s the chance of meeting someone this rich again? If I stay with Katie, she gets a husband and, I hope, a family, while I get a lifestyle that most people would kill for. It would be a secret deal with my conscience, if you like, though Katie would never know that. But my fear is that I would live to regret it, which would be the worst secret of all.

Do you live with a family secret? How has it affected your life? Do you still struggle with it? E-mail us at familysecrets@thetimes.co.uk Or write to us at: Family Secrets, times2, 1 Pennington Street, London E98 1TT Anonymity guaranteed

Do you have advice for this writer? If so, you could either e-mail us on the above address, or go to: timesonline.co.uk/relationships Your advice may be printed next week

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