Fake friends or no friends at all?

I've been friends with these people in my school (I'm in Sixth form now) for quite a few years now and it's been more or less the same ever since day one.
I'll give a few examples.

It'll be just me and this one friend in particular and we'll be in the library working and I'll be trying to read or write an essay and he's constantly talking about irrelevant crap or gossiping about people I don't care about. If I politely say "I'm just trying to work right now..." he'll claim that I'm in "one of those moods again"

Or, even if I don't say anything and just let him talk on and on about whatever, as soon as our other friends come, he just turns his back to me and talks to them instead. Leaving me to literally just sit there. It's like as if he gets bored of me and needs a new toy to play with.

Today, I came out of my lesson to the common area and they were all talking and didn't even utter a word to me. Then when break time ended, they all went to their lessons apart from me and the same boy mentioned above as we had a free. I was reading but he doesn't respect the fact that I'm busy because I do more vigorous subjects than him. As soon as it was lunch and everybody came to the dining room, he just starts conversations with everybody without including me. I know it sounds childish. I'll just sit on my phone and read the news, and then he turns to me and goes "what's up?" I just said that nothing was the matter and carried on reading and he said "well you can smile then!" I just ignored him. He assumed that I wasn't talking to him for some reason when really it was him. I came over to him to sit down and stood by him for a second and he never even looked up at my computer. So I just left.

They're not like this everyday though, sometimes there are days that are great.

Should I ditch?

It's better to have friends than none at all depending on how they treat you of course. But i think you should explain to him that he does these things like constantly talking when your trying to study or read and also tell him when other people are around he completely ignores you and does not include you in the conversation rather than just ditching without an explanation.
A few years ago when i had a job I had a work colleauge like that where it would be just the two of us eating lunch in the dining room then as soon as a group of other people came and sat on a different table she got up to sit with them but at least she had the decency to tell me she is going over to sit with them but it still made me feel like **** sitting on my own. I could have gone with her but i did'nt because i was shy and there were too many people but it did not feel good that she preferred other people's company .

But your friend is oblivious to what he is doing unless you tell him and point out the things he does. Sometimes telling people the truth hurts them more than it hurts you to have to tell them and they get defensive, offended or resentful for you being honest then decide to be an ******* by not wanting to be friends anymore because they are up themselves and think they are better than you as i discovered this last year before christmas with a friend i have known for many years.

So rather than ditch him just tell him the truth, if it changes your friendship where he stops talking to you all together then you know he was never really a friend to begin with because real friendship is about always being there for someone not just wanting to speak to you when your both alone and ignoring you when you are in a group.
Plus i do not like his sarcastic comments of well smile then and saying your in one of those moods again so you are right to ignore it when he says those things but it would drive me mad if someone kept making silly comments like that to me too
Everyone acts in a different way and sometimes they can't help being selfish and self centred but at least you've got a friend who wants to talk to you sometimes as most people on this forum have got no friends at all.