I'm 30, and my best friend is 75. She's shaped how I approach relationships.

• My parents introduced me to my best friend when I was 19, hoping she would be a good mentor for me.
• Now, more than 10 years later, I consider her my best friend.
• Despite our 45-year difference — or perhaps because of it — we've learned so much from each other.

Heartbroken after being dumped by my then-boyfriend, I met a friend for dinner.

As she sipped sparkling wine, her coral-manicured nails and diamond bracelets glinting in the light, she told me, "He wasn't right for you. I think you were more interested in his Highland cows than him."

Only Gill, my 75-year-old friend, could get away with saying that. Tears quickly turned to roaring laughter as we toasted to moving on — and to not needing a man to acquire farm animals.

At 30, people often say it's nice that I have an "extra grandma," but I quickly correct them — no, she's my best friend.

We met over 10 years ago

We met through my parents when I was 19 and studying for a degree in fashion. They thought Gill, a former fashion industry professional and principal, would be a great mentor during my final year.

At the time, neither of us expected the friendship that would blossom from just a handful of email exchanges. Soon, we were meeting regularly to see exhibitions, go shopping, and set the world straight over six-hour lunches. No problem was ever too big to be solved over a bottle of pinot grigio.

Now, over 10 years later, we're closer than ever, and our friendship has expanded to include her husband, Howard, who has just as fun and vivacious an outlook on life. He's officially one of the girls and, luckily for me, lets me third-wheel their retirement.

Unlike friends my age, Gill's blunt but caring advice — especially when I've needed it most — taught me that it's better to be upfront than to avoid difficult truths. This has shaped how I handle not just friendships but career decisions and romantic relationships, as well.

She often tells me our friendship is a tonic and that she struggles to relate to others her age who insist on slowing down and seem to lose their joie de vivre. That's something Gill will never do.

We've both impacted each other greatly

The biggest lesson she has taught me is that aging is not something to be feared. I've watched her embrace it glamorously over the past decade, always wearing clothes she's made herself: wool coats, silk dresses — you name it.

Recently, before undergoing surgery, her surgeon took it upon himself to offer to "wipe grease" from her face, to which Gill replied, "I'll have you know that's a $200 bottle of Dior serum on my skin."

She learned to paint in her 60s and continues prioritizing her well-being with weekly yoga, Pilates, and coffee mornings with her gal pals. Through osmosis, my confidence thrived throughout my 20s as I modeled my independence on how Gill lived her life. Prioritizing my career, always maintaining separate bank accounts in relationships, and having multiple hobbies and interests — these are all things I value, thanks to her.

Intergenerational friendships, like mine with Gill, can broaden your worldview and offer an emotional richness that only comes from someone with real-life experience.

At its core, friendship is about accepting each other as we are, yet we're often quick to judge. Had Gill and I done that, I would have missed out on one of the most defining friendships of my life.

When we first met, I was graduating from college, one of the most pivotal phases of my adult life. Now, as I navigate a relationship that spans continents and have moved away from Gill to find new roots, we continue to support one another, even as our circumstances shift. I look forward to seeing how our friendship will continue to evolve, and, if the fates allow, I hope to be someone's Gill one day.