Break up help

Me and my boyfriend, well now ex, have known each other since October 2011. We had spoken on/off over the years but it was never the right time. Then I came out of a horrible relationship with my ex before him, and we started meeting up. And I have never felt something so right in my life. For months and months it was amazing, but then we started to argue over stupid things, all of the time, and he ended it 12 January. For 2 months I waited for him whilst he got himself together and wanted to try again, we saw each other every day in this breakup. And then 8 March he said let’s give it another go, and again for ages we were fine and the arguments started to creep back in so May 31 he ended it.

I’m 21, and he is 23, so we are both still young. I am his first relationship, and also found out last week, the only girl he has slept with, but he always said he felt embarrassed to tell me, which broke my heart. I love him so much, and he loves me, and said he would happily have a future with me but we just can’t get along.

What can I do?

I know he is the one.

I know he is the future dad of my kids.

I know I’m meant to live with him.

I know he’s the one I’m gonna marry.

Everything.

He is the one.

PLEASE HELP