My Elder Brother's Fiancée Is In love With Me

Honestly, i don't know what to do.....My elder bro wife to be is dying for me & my only brother who trusted me so much never notice it.

All this started when i celebrated my birthday last year & my elder bro funded everything such as drinks,foods etc, except the cake & the party house decoration which was funded by his fiancee. She even bought me a 'Rolex stone watch' as a birthday gift right before my brother.

I never knew that she had feelings for me then, until one fateful morning, when she blew it open by sending me 'morning love texts' confessing that she loves me & will do anything to make me happy. First time i saw the text, i thought it was a mistake, that she wanted to send it to my bro but when i call to confirm, she told me that the text was for me. At first i couldn't say anything, i was speechless, never believed it until when i met her one on one in my bro absent that she make it clearer to me that she was madly in love with me & even ended it up with a hot kiss.

Honestly, my brother's fiancee is truly beautiful that no man can resist her easily & my bro who trusted me so much never noticed dis.......

what should i do? Should i make this known to my bro or should i keep it secret & enjoy her ?

Pls am confused now, need your advise!