Your significant other just proposed to you. What do you do next? For many of us who did not grow up with  social media, you might set a meeting with your extended family and announce the engagement. At the very least, you'd make a phone call. Yet, a new study by social media management company Sprout Social found that most people these days use social media to announce major milestones--a surprising finding to say the least.

79% of those surveyed said they share milestones on social media first. 75% said they still do that in person. Texting and making a call rank a bit lower. Less than a third send a letter.

Facebook is the preferred sharing platform for milestones like getting engaged, having a baby, or graduating from college. Instagram ranks second, followed by Snapchat, Twitter and YouTube. (I'm not too surprised Twitter is ranking lower these days, since the company can't seem to get past the online abuse problem and stagnant user counts.)

What it means is that the sinews that connect us are going virtual. If you are getting married, having a child, changing relationships, or heading off to a new job, it's more likely than ever that you'll turn to Facebook or Instagram first, according to the survey.

As the report indicates, it's an important finding for small companies trying to reach an audience. First and foremost, it's a simple business lesson--go where people are the most active and follow the trends. If you share news with a select few in person, but you mostly let everyone know on social media, then it makes sense to gravitate to that domain.

I remember trying to establish a presence on Twitter back in 2010 or so. It seemed like dabbling back then, a side effort that I wasn't taking seriously. Other workplace and cultural touchstones had not quite developed back then, either. Email was still the best way to communicate, not a collaborative environment like Slack. For entertainment, you either went to a movie or watched a major network like CBS. Streaming was not quite a thing. Even texting, as common as it is now, was still gaining a foothold.

When you think of consumer trends, it's important to drift toward the avenues that are trafficked the most and tend to take up the most mind-share. In the same study, Sprout Social found that about half (or 48%) of respondents were willing to make a purchase related to a life milestone after seeing it on social media. That's an excellent finding for anyone trying to establish a marketing presence, because it means engagement (ahem) is high. There's a "see a milestone, respond in kind" mentality.

Think about how that might work if you are a retailer that caters to wedding or grad gifts, a company that makes high-end gifts, a recruiter, or if you're a college trying to reach a younger audience. Targeting ads on Facebook makes a lot more sense for a jeweler these days. Colleges should focus on Instagram. Matching your marketing to a trend is an age-old practice, but if you learn anything from this study of milestones, it's this: Social media is not a trend. It's crossed over from a cheap way to do marketing to a major platform for reaching a key audience in ways that were not possible before. If the first thing people think of when they reach a milestone is "I better post this on social media" before telling people in person as the study found, it's an even bigger wake-up call for marketers trying to figure out how to get attention for a new product.