What do u think? no silly answers please?

I left my husband a few years ago we seperated very amicably and stayed friends...a yr later i met my now fiance and became pregnant...even tho my ex also has new fiance and new life hes became very strange pretends to be my friend but sends nasty emails and calls at strange times in the night both him and his new gf...i changed number and email addy but now hes putting messages up for me in his profile in friend reunited...i find tis all a bit odd and dont get why hes all of a sudden doing this....any ideas?