A lot of people forget how taking a walk in nice weather alone is a very uplifting. It gets the serotonin working, and it's not super taxing. It puts life in perspective. You see things passing by and the majesty and timelessness of world. And it's totally free. Taking a book or a CD player or reading or writing for few hours is really taking nice care of yourself. When you're in a relationship you don't get around to doing that. - Delphine Hirsh

People are always saying relationships are so complicated, they are yes! I am not saying they are not... but I believe they are only as complicated as you want them to be. Being a relationship take two people, who decide to merge some or most aspects of their life together, and that is it. The fact that it only takes two people makes it complicated as in, there might occasionally be conflict of interest, however if you and your partner are fully exclusive, you only answer to each other, i.e. "baby what you got planned for today" answer: 'might go here and there and here then back to you'. during the day a few texts, maybe some phone conversations the next day comes. If you want to be with the person genuinely and you really like them is fairly easy and simple. Unless you are hiding something, i.e. you are a partner to another relationship ..lol.. *get it?

The fear of being an old maid made young girls rush into matrimony with a recklessness that astonishes. - Louisa May Alcott

Being single on the other hand, can be seen as uncomplicated since you are a free person, but I sorta disagree, it like you have a relationship with the whole world... I personally don't think anyone is ever really single like really single... there is the odd bloke/girl that you talk to every now and then. 
But the main issue is that when you are single, you owe everyone you *talk* to something. They might not utter it, but its there, for instance girls... when a guy take you out , and you enjoyed the date and to you everything went well, don't you sorta expects him to call you? (lets be honest) 
But he might not see the need to call you at least, he is not your boyfriend, so he doesn't need to call you. Whereas you actually liked him but since you lot are not together, you probably put on a front and don't call him, see unnecessary stress.

"You do not need to be loved, not at the cost of yourself. The single relationship that is truly central and crucial in a life is the relationship to the self. Of all the people you will know in a lifetime, you are the only one you will never lose."

Another thing no-one actually believes you when you say you have are not single, I'm I making sense? Like you are single and  a guy approach you, you are uninterested so you say: 'I'm in a relationship'. I don't know if I'm a terrible liar, but it doesn't seems to work? they still follow you and try to get your number and sometimes the only route to escape is to get rude, which  might land a very angry and embarrassed guy, (I don't want to even know what they will be capable of)
[Being] single is better... for the simple reason that I wouldn't want to change no diapers. Of course, if I did get married, I'd figure something out. I'd just phone my mother and have her come over for some coffee and diaper changing. - Kirsten,

Another complication, when a guy takes you out some of them actually expects something because they spent some little money to take you out. I see it this way, you saw me you liked what you saw, wanted to get to know the person behind the face/body you saw, I thought you was a decent bloke, I allowed you to take me out, you are actually quite self centred and I don't wanna go out with you no-more, so I won't pick up your calls *evil laugh*

Being single is a liberating status, but do we ever have total freedom? At least when you are in a relationship is voluntary and all complication are accepted, usually expected. Single on the hand is just too much stress, I might be talking total rubbish, but let me know what you lot think. 

What you are as a single person, you will be as a married person, only to a greater degree. Any negative character trait will be intensified in a marriage relationship, because you will feel free to let your guard down - that person has committed himself to you and you no longer have to worry about scaring him off. - Josh McDowell