What's your advice for not getting hurt in my relationships? I say don't take them seriously from the beginning. Humans are fickle creatures and their

If you don't take them seriously, then what's the point? Your relationships wont have any chance to get very far that way, plus the other person has a chance of getting hurt if they're taking it seriously. Unless you talk about it and decide you both just want to keep it casual.
I'd say just be careful with who you choose to get in a relationship with but you've also just gotta take chance sometimes and hope for the best.

Humans, by nature are overly emotional and extremely expressive within their own personal way

Proceeding with caution is seldom bad advice...