Sugar and Alcohol Free Cocktail

In Rome last week for a fabulous, mind blowing experience but, equally, as a person eating what can be called a 'special diet' it was a major challenge!
And it started at the airport.... there are coffee shops selling the obvious range of drinks, and cakes and pastries to go with them. Full of sugar!
There are self service restaurants selling pizza, coated chicken pieces, burgers in white processed buns, chips, sandwiches in white baguettes etc etc. All refined carbohydrates are treated by the body as sugar- I couldn't eat anything!!
I managed to find some cashew nuts ... eventually ; that was literally it!
In Rome itself there were restaurants galore all advertising fantastic, authentic pasta and pizza dishes, especially for the tourists. Italian wine is rather tasty too, as are the coffees... I could have none of it.
We ended up in the Hard Rock Cafe one night; suffice to say that wasn't my idea!! But, as it turned out not only was my faith in human nature increased, but the meal was tasty too.
After perusing the cocktails menu, a strawberry daiquiri style drink caught my eye- it included fresh pureed strawberries with sugar, lemon juice, basil, lime, lemonade and alcohol. Ok so I couldn't drink it but wondered whether it could be adapted for me!
The children cringed as I questioned the waitress (they hate it when I try to deviate off menu, which is generally always!) . She kept blocking my suggestions until eventually, realising how desperate I was to have something other than mineral water, she said leave it with me.
She was gone for ages, and eventually appeared, tall glass in hand full of a pink looking liquid. She presented it to me, said she'd made it all herself from scratch and it contained NO alcohol and NO sugar. It did contain puréed strawberries, lemon, lime, sea salt, sparkling mineral water and basil. And a straw.....
Wow! It was fabulous and so was the attitude of the waitress. I was bowled over that she'd gone to so much trouble, and thought completely out of the box. Suffice to say I smiled through the meal and her tip was rather large!
Must try replicating it at home.
Rx