I have begun to love someone since sometime in the past.
I have fallen in love with you since XXX
I have been in love with you since XXX
I have had a crush on you since XXX baby. have a crush on you 是在一首歌里面听到过的
爱上 本身就是 fall in love 你为什么不想用这个呢
I lose my heart to somebody from....
我爱上某人从某时开始
I gave my heart to Jane from last summer.
I lost my heart to Tonny in a shining spring .
I grew tender of Jack from the year 2000.