I thought it was fun

I met a guy online a few weeks ago. I started a long distance relationship with him. At first i did it for fun, not serious. But later, he is just so sweet and i can’t resist. I think i’m falling for that guy i’ve never met. I facetime with him. But these days he’s acting very cool and he rarely text me. Like today, he just texted me that he was not very well and he loves me. He said he loves me but his action doesn’t. I know this relationship won’t work. As much as i want to end this, i can’t. I’m attached to him. Now, i’m afraid that he’ll leave me. I thought i wouldn’t fall for him but now this is not what i thought, i fall for him. Now, he’s acting very cold and i feel sad. I can’t even breathe properly, beside i have breathing problems. And it’s funny how i’m feeling for the guy i’ve never met. I know he may want something real, like real relationship in his life. And i hope the best for him. But i’m afraid that he’ll forget me and leave me when he find someone in his real life because i’m just a girl he met online, nothing more What should i do?

I asked him if this relationship is real because it’s too good to be true. But he always reply that he really love me but he doesn’t know why. But his actions doesn’t say like this. I’m falling for him and i don’t know how to stop. I think i love him. I know this is crazy but..i can’t help. I feel so low if he doesn’t text me. What can i do? What should i do?