how...?????

Not sure i am best to answer that as it hasn't happened to me and i don't know fully how that would feel, but first thing that sprung to my mind was bereavement counseling. that and keep your family & friends close by, don't hold it all in and take things slowly.
you might not ever really get over it, but you will be able to build your life back up and carry on, in time.

I am sorry you lost somebody so special.

I send my best wishes to you and strengh of spirit too,unfourtunatly I have no practicle advice for you as I have never been there.

I second the advice on seeing a professional in helping you with emtionions that you may not fully understand.

I know that my family have been a bedrock for me in tough times and if you are as lucky as me let them help you through this.

One thing that can't die however is the love you felt for each other that's as alive as it ever was.

All the best my friend.

There are things in life you never get completely over.
What happened to you is really hard and I don't know if you'll ever get over it... However, in time, it will probably hurt less and not so often, especially if you manage to go on with your life.
However, it probably reshaped you as big things in life do. So you can say one part of it will be with you forever, in one way or another.

There's probably nothing that could take away your pain right now... Only time can soften it.

Remember this, if you can't smile for yourself then smile for someone else.

For a start you never will "get over it" - the event wasnt the measles.
A fella of mine his wife died in his arms, literally, he nursed her thru cancer. I can only tell you what he said/did. It was 8 yrs before he starting courting again (me). We were friends before and I knew the situation. He told me all about her, how she died etc and I went with him to light candles and every anniversary we talked some more. I never thought of me being 'second best' or that he was not over his loss, i just dont see why he should pretend she didnt exist just because he was with me.
He still to this day misses her at times, he cries for her, he laughs when sharing the memories of happier times with others.
I doubt you will ever 'get over' her and this tragic event. Just that you will find people in your life who allow you to cherish your memories without jealousy or them feeling uncomfortable and the days get lighter and the pain becomes less severe. (thats the same as losing any loved one in any circumstance).

That's a very touching story, RG.