I don't even know where to start.

The thing that has really got me down recently is this bloke I've been seeing (about 4 months, we have a friends with benefits type of thing going on because he has never done a long term relationship and I've not long come out of one), he can be very sweet and thoughtful, make me feel on top of the world, but then we have these horrible arguments.

He can be very arrogant. If I try to explain to him that something he has said has made me feel intimidated or upset, he turns it around and I feel like I should say sorry to him for saying anything in the first place. When I've spoken to him about being nicer, he says he will not change a single thing about himself.

Tonight he told me I make his life a f-ing nightmare after I said that I thought it was mean of him to say something nasty about someone I look up to. Exact words.

I know I shouldn't keep seeing him based on what he says, but I feel like if I did stop, I would regret it because when we are good, we are really good. It feels impossible for me to come out with the words, I don't want to do this anymore.

I know its not the biggest problem in the world, but I just needed to talk about it. I suppose I'm hoping that someone out there can relate in some way or just tell me its not the end of the world or something lol!

Honesty, trust, respect, communication, common goals. Future or not?

It sounds like you don't have your agreement straight.
Is there one? FWB? Who coined that? You, or him?

Sometimes we have to get to the bottom of what we are doing & why. Who we decide to partner with & why.
If this isn't working, then stop the expectations, fix it mutually, or split.
Is this good for you? Is he all in? Doesn't seem like it.

You want more. FWB.
Selfish expectations can kill things.

I say stop trying so hard, shop around. Forget him for a while.
You may want one thing, but... That doesn't always happen.

Things don't always turn out how you want.
But, you are in control of what you do. Who you want in your life.

At some point, you got to do what's right for you. What do you want?

4 months? stop stressing.
Stop rushing. Take your time.

I understand what you're going through. You have connected with this bloke on a physical ,spiritual level (where indeed we are all one in spirit) but on the soul (phsycological) level, there's work to do. It appears from what you've said that he is very self centered, and hasn't given you any reason to think he cares about your needs(feinds w/ benefits).

The only person you have the power to change is you. If you do what is beast for yourself, in the long run you will win self respect (and perhaps he will admire you for standing up for yourself). Be careful to not allow him to tear down yourself esteme.

You said you point out his mean comments, which he then turns around on you... perhaps he's a bit masochistic? Most people will become defensive when their faults are pointed out to them. Counter-attack is a form of defense,it is also a sign of immaturity.
It sounds like you are ready to find a relationship that is more genuinely loving (not just physically enjoyable). I think from what you've said, you realise you may need to move on.

I would gradually take more time for myself, try to develop other activities outside of this relationship. If he cannot deal with honest communication and be responsible to you for the relationship you have created together, you need to take care of yourself.

Let the @$$hole go and part away, you deserve better.

Boy do you need a better life with better friends. FWB, is not a relationship, it's a use, and be used free sex romp. Think better of yourself, and do better FOR yourself.