This feels like a dangerous article to write. It's a subject on which many people think I don't have a right to an opinion. Although I've tried to keep my views to myself thus far, I've started to wonder why I should. As Trinculo in The Tempest says: "I do now let loose my opinion; hold it no longer." I don't want Scotland to leave the UK, and I want to be able to talk about it.

Over the last six months or so, as I have watched the yes campaign gather momentum, my concern has increased. "But what's it got to do with you?" people ask. "You're not Scottish. Why do you care?" True, I'm not Scottish, not enough for any "real" Scot to care what I think. I have a Scottish name, and my father's family were from Loch Lomond (having originally come from Stroma, a tiny island off the north coast of Scotland). My father went to school in Scotland, always supported Scotland at rugby, and celebrated Burns night every year. But I was born in England, and for professional reasons I live in London.

I have always considered myself British. But if Britain is about to be redefined as a country that doesn't include Scotland, then I don't feel British at all. Living in a country that has Scotland as part of it is an essential part of who I am.

Over the last few months, I have realised I have very strong feelings about all this – but it seems there is no approved outlet for them. I am supposed to just sit here and take whatever happens in the referendum without saying a word. It feels like being left by a lover I have lived with for years and not being allowed to make any contribution to the discussion about our future.

Now, adhering to the theory that one might as well be hanged for a sheep as a lamb, having let loose my opinion, let me dip my toe into the shark-infested waters of criticising the yes campaign.

This criticism rests on one key point: the yes campaign is based on an "anti-posh south-easterners" sentiment. It's anti-Tory; it's anti-Cameron and Osborne; it's anti-Eton. The truth is, it is not pro-Scottish: it's anti-London.

Whatever one's political leanings, it must be admitted that if this campaign were being conducted under a Labour government, at a time of prosperity, the yes campaign would have found it far more difficult to gather the head of steam it has. Its entire rhetoric rests on escaping Tory rule – which, frankly, is a sentiment shared with millions of other UK residents, and seems an insufficient basis on which to conduct a debate with such massive ramifications.

No one is under any illusion that the Scots' dislike of the southern English middle class is anything other than profound. Anyone, like me, who speaks with what is known as received pronunciation, and who has spent any time in Scotland, knows what it's like to be on the receiving end of anti-English feeling. (I was in Orkney once, staying with a local doctor while my theatre company was performing at a festival. One night, friends of the host had to be ordered out of the house for refusing to address me directly – because I am English.)

But this referendum is too important to be fought on such a narrow prejudice. The yes campaign talks about not wanting to be ruled by a party its supporters didn't vote for. Well, what about the vast majority of people in England, Wales and Northern Ireland, who didn't vote Tory in the last election? The yes campaign detests the public school elite – but what about the millions of people in Britain who aren't public school educated? The yes campaign hates being ruled by London. Well, what about the 50 million people who live in the UK but not in London?

Let me now criticise the terrible Better Together campaign. It needs to do something fast to prove that the UK population feels much as it does about the current government, the status quo and the future. This isn't a fight between Scots and English; that's an invention of the yes campaign. Better Together needs Welsh voices on board, and geordies, Liverpudlians and Mancunians. The "rest of the UK" is so much more than a few smug Londoners, despite what the yes campaign would have us believe.

I have talked to many friends about all this. I have an English friend who has bought a house in Scotland so that she can vote for independence and live in what she sees as a Tory-free utopia. And I have many Scottish friends who don't live in Scotland (because they work in industries with no base there), who can't vote in the referendum and are frightened to voice their opinion for fear of intimidation by the yes campaign. This seems ridiculous. These are people who were born and brought up in Scotland, whose families live there, who identify wholly as Scottish. Not only are they unable to vote on the future of their country but they are also too nervous to say what they really think about the whole vexed issue.

This isn't a general election. The people who live in Scotland are deciding the fate of that country for ever. There isn't going to be an opportunity for a change in five years' time. Let's open the discussion up to everyone who cares about it, without fear of intimidation.

I, and millions of others who don't live in Scotland, fervently want it to remain a part of the UK. Scotland, let us press you to our collective bosom and say to you, in the words of that poet from Warwickshire, that "other strains of woe, which now seem woe, Compared with loss of thee will not seem so".