Don't exercise for the likes, the comments, the compliments on social media, because they are not happiness, they might not always be there for you, and it should not be the main thing that drives you to be fit, and healthy. Instead, exercise because it makes you happy, makes you confident, and makes you feel on top of the world, especially after you finish a workout that you didn't think you'd get through.
You may notice that I'm always posting my workouts on Instagram more often than not, and I'm not saying you shouldn't, but I do it for myself, to hold myself accountable. If you have the right reasons behind it, then by all means post away! While the likes give me some motivation to workout, if I don't feel like working out one day, I won't. If I feel like working out, I do. If I only worked out because of the likes, I have a feeling it would lead to a ton of disappoint me. What would I do if I let likes define my happiness? If I only received 5 likes on a picture that showed how hard I push through a workout - I think if the likes were my only motivation to workout, I'd give up.
Don't let the likes define who you are, your happiness, or even be the motivation to workout. It doesn't matter. You workout for you, and that's that.