They're never ready for you to leave: When it's time to say goodbye, they either ask you to stay or pull you in to endless hugs if you've really got to go. You're their favorite person to spend time with and they genuinely enjoy your company.
They go out of their way to be there for you: It doesn't matter that your car broke down in the middle of the night or early in the morning — you can depend on them to help you out. They do you favors because they want to, not because they expect something in return.
Every time they see you is like it's for the first time: They just can't get over how lucky they are to be with you and shower you with the same amount of love as they did when you first started dating.
They call/text to say "I miss you": They're not overly clingy, but they wouldn't mind being able to spend every second with you if they could. Your SO often lets you know how much they miss you and are already wondering when they can see you next.
They always want to make sure your relationship is in good standing: If a problem arises between the two of you, they want to fix it right then and there. They're not one to ignore issues because they value the state of your relationship.
They're vocal about their appreciation for you: He or she often tells you how thankful they are to have you in their life. They don't take you for granted in the least bit and are grateful for every little thing you do for them.
They have heart eyes when they look at you: You catch them staring at you with adoration and they don't hold back on compliments. It's not that they're stuck on your physical appearance, but more on how amazing you are to them.
They're interested in your life: They want to hear all the details about your day, what your current projects are, the gossip at work, etc. Things that would normally bore anyone else are interesting to them because they love learning more about you.
Your safety is everything to them: They can't stand the thought of anything bad happening to you. They worry about you getting home safely late at night and would rather escort you themselves than sending you away in a cab.
They do thoughtful things for you: It's not unusual to be surprised with your favorite snacks or a glass of wine waiting for you after they've heard about your tough day. Little things always remind them of you and they love making you smile.
They put you before themselves: They make you a priority when necessary and would rather make small sacrifices to help you or make you happy.
They want to take care of you: Whether it's when you're sick or upset, they want to be the one to make you feel better. It's not about babying you, either; they simply want to provide you with every type of support you need.
They want you to hang out with their friends: As much as they cherish your time together alone, they also want you to be a part of their social group. They want those closest to them to know how awesome you are.
They're not interested in anyone else: You never have to worry about wandering eyes because their focus is always on you. They're not even tempted by others and know that they have a good thing right here.
You feel nothing but loved: The way they touch you, hold you, kiss you, look at you — it all comes from a place of love. You never have to second-guess their feelings for you because they show you in every way.