The couple, who married last year after a 12-year engagement, announced their win at their local pub in Scunthorpe where they put on a free bar for all their family and friends today.
And with their wealth now doubled, they can swap their bungalow for a seven-bedroom mansion with swimming pool and up to 20 acres of land.
Mr Long, who has been previously married, said: "We don't have a champagne lifestyle. We still live in a mobile home. We've been there for 13 years in our static caravan.
"That's changed now though, we are planning on moving somewhere else. We've had a bit of luck. It doesn't have to be a big mansion, it just has to have a games room and a bar for me."
Mrs Long, 63, who grew up in Berwick upon Tweed near the Scottish borders before moving to Scunthorpe aged 14, added: "We've seen a couple of places we would go and have a look at.
"We wouldn't move far away though. Our main priority is to stay near family and friends."
Explaining how he won again Mr Long had passed his local newsagent before the Friday draw and thought "I'll have a go" and said today: "I always knew I'd win, even the first time. I just had a feeling it was going to be me".
The couple, who don't have any children together, then checked the numbers on the morning afterwards "on Teletext" and Mrs Long had screamed: "You said you'd do it again and you have!"
Mr Long said "you never know" when asked about winning for a third time.
"They say things come in threes, don't they?" he said. "Third time lucky and all that.
"You never know. You've just got to believe that one day you're going to do it. We've done it. To believe we're going to do it again. It's happened. Could it be a third time?"
His wife, who was also previously married with three children, said: "He probably will."
Last time the HGV driver and his now-wife won despite throwing their ticket in the bin in 2013.
He then "had the urge to fish it out" and was shocked to discover it was worth £1 million.
Mr Long said today: "I tend to play when I know there are lots of prizes on the go.
"Last time I knew I had a good chance because there were 100 prizes of £1 million. Last Friday night I was passing the local shop and saw there were 10 £1 million prizes on EuroMillions and a nice car and thought yeah I'll give that a go.
"Got to be worth a few lines and I got five using my usual numbers.
"On Saturday morning I sat down in front of our telly and started checking the numbers. On one line I'd matched two numbers and one star to get £7.20 and thought that's all right.
"Then I checked the raffle code s- something I've learnt to do automatically since winning last time. After a few moments I very calmly called Kath in and said 'Have a look at this. It's there. Look. Read that line'."
Mr Long said his wife checked the television and went online, adding: "Then she went up right close to our television on the wall, put on her glasses and stared really hard at the raffle numbers. It seemed ages and then she finally said: 'You said you'd do it again and you have!" Everything has been a blur ever since.
"It's definitely taking longer to sink in this time!"
Bookies told MailOnline today that they could not find any bets on the planet that could match the 283-billion-to-one odds of a double lottery win.
But one said an example of a million to one gamble would be for future king Prince George winning Wimbledon while also captaining the England rugby and cricket teams.
A Camelot spokesman said: "This is an extraordinary situation where somebody's been fortunate enough to win twice.
"As you can imagine, we see winners who win once who are very, very shocked. It must be even more shocking to win twice."
Two years ago, Mr Long, who was working as a HGV driver for a local transport business in Scunthorpe, nearly missed out on the big win altogether.
He thought he had won just £2.70 and with the ticket in the bin he nearly did not bother to claim the winnings.
At the last moment he decided to take the ticket out with him as he needed a newspaper.
"I had to fish the ticket out of the bin that time and found when I got to the shop that it was worth a heck of a lot more.
"That win was fantastic and couldn't have come at a better time. Times had been really tough and I had been really ill for three years, unable to work leading up to it.
"I lasted three days at work and then took early retirement. We've had an amazing 18 months, have been able to treat the family, buy a new car and even finally get hitched - after being engaged for 12 years.
"But I always told everyone that I'm gonna do it again. I just knew it would be my turn again some day. Now it has and we just can't believe it," he said.
With their last winnings they bought Mr Long's mother a static caravan. He said: "I bought her a mobile home when we won the first time round. We have lived in one ourselves for 13 years so we bought one so she can live right next to us.
"She keeps rubbing my shoulders for me to buy her a ticket because I've been lucky. She plays the lottery herself but she's never won."
His mother Joan, added: "I just thought, how could someone do that twice?"
"Dave is donating some of the money to Lindsey Lodge Hospice in Scunthorpe, which is fantastic.
"I'm nearly 82, but I volunteer for them once a week. I've done work for the Salvation Army, too.
"Dave bought me a mobile home with his first winnings and I'm really close to the one he shares with Kath."
Mr Long says he is not a fan of travelling abroad and hates the idea of flying, but he feels it is time to book a cruise.
"Kath and I had a fantastic wedding last year but we never took a honeymoon because I'm just not keen on the idea of flying.
"Kath would love me to book a Mediterranean cruise and I think I have just run out of excuses," he joked.
At that time, the couple had been together for 18 years and engaged for 12 years.
