You shouldn’t make one person your whole world because if you break up you’re going to feel like you have no reason to live. You’re going to feel like your whole life is falling apart. You’re going to have an extremely hard time getting over them and moving on with your life.
No, breakups are never easy, but if you have other beautiful things in your world aside from your relationship, you’ll still have something to look forward to each morning. You’ll still have little things that bring you joy. You’ll have an easier time finding hope after you part ways.
Even if you end up sticking together until death do you part, you shouldn’t make one person your whole world because you’re supposed to be your own person. Love isn’t supposed to take away your personality or your dreams for the future. You can still act as a team while acting an individual. You can still take your partner’s opinion into consideration when making opinions without letting them rule over you.
You’re not supposed to agree with your partner one-hundred percent of the time. You’re supposed to have your own thoughts and ideas and opinions. You’re supposed to be two separate people coming together, not clones of one another.
You shouldn’t make one person your whole world because there’s more to life than love. You should have friendships that make you happy. You should have hobbies that make you happy. You should have a career that makes you happy. You should have plenty of different things that contribute to your overall happiness. Your partner shouldn’t be the only good thing in your life. If they are, then you need to make some significant changes. You need to take a look at your priorities and see what changes you can make.
You shouldn’t be putting pressure on this person to be responsible for every ounce of your happiness. That’s not fair to them. And it’s not healthy for you.
You don’t want your sanity to hinge on whether this person is treating you well or not. You don’t want to make one person your whole world because everything can change in an instant. If you lose this person, or even get into a fight with this person, you don’t want to feel like life is pointless. You don’t want to feel like you have nothing left that matters.
Your partner should be a wildly important part of your world — but they shouldn’t be your entire world. They shouldn’t be the only good thing you have going for you. They shouldn’t be the only reason you’re able to climb out of bed each morning.
You should create a life that makes you happy. Not just your love life. Your entire life.
Make sure you put as much effort into your hopes and dreams and hobbies as you’ve been putting into your relationship. Make sure you don’t forget about the other things that are important to you. There’s enough room for your partner and for everything else that matters to you. 
