It's a long time since I met you last.

Long time no see.　　Sorry I haven't been couldont come here.
Actually, I ama member of the belong student council.
There was  had a big event,and I voted for/chosed the chief, but my the members didn't act, so I conducted ran it alone. I feel very tired.><

I communicated with a group outside the university with a Power Point presentation. i had communication group out of university alone,(for example,a prefectural main police office)
i had make PowerPoint and slide alone...

but Now, I feeling of freedom from worry or disappointment!
The long fighting has come came to an end at last!!

I have been successful. i can it make sucsess.

I'll answer your return you many message from this week, and begin again. 
and restert.

Thank you for thinking about me♡　ではまた！

(of cause, (If you find my any mistakes,please tell me.)
(this time, i don't care about grammer&spell. may be many misstake heddin in this note)

It's a long time since I last met you last.

Long time no see. Sorry I couldn't come here.
Actually, I was belong to student council. I had a big event, and I was chosed choosen as the chief /president. but my members didn't act do the work.
So I ran it alone. I feel very tired><

I had communication group out of university alone, (for example, a prefectural main police office)
I had to make Power Point and slide alone...

But now, I am feeling of freedom from worry or and disappointment!
The long fighting came to an end at last!!

I can it make success.

I'll return your many messages from this week.
and restart.

Thank you for thinking about me♡　ではまた！

(of course, if you find my mistake, please tell me.)
(this time, i don't care about grammar & spelling. this note may be contain many mistakes heddin in this note)

I sympathize with your busy work. But fortunately it had ended. 

Your English is good. Just a bit mistakes here and there. But that's okay! Good luck!  :D