Given that Christians, Bahai, Muslims, Rastafari, and Jews all worship G-D, why can't they all just get along?

Great question! Sadly the mass religions are man made, having lost much of the original spirituality. Deliberately persecuting genuine people with knowledge and deeper understanding such as the Cathars, for example.She is too, I expect. 

Straw Man fallacy.  All those you mentioned do not worship the same God.

Only the Catholic Church has the fullness of truth.  We are to worship God in the way He wants to be worshiped.

Why can't you spell the name God instead of G-D?

Is it possible that non-christian faiths/religions are actually worshipping other "gods" and not Almighty God of the bible?

The bible does talk of people worshipping other "gods" Pharaoh and the Egyptians in the O/T as an example which brought Gods displeasure on those people.

For the last 2000 years God is showing his love to this world through his only begotten Son Jesus Christ who died for the worlds sins (John 3:16)

While God is not displaying his displeasure to people today who worship other "gods" it still doesn't mean he loves what they do!

Do these other religions you mention teach and believe that Jesus Christ was Gods only Son and that he died for their sins so they could be forgiven and have eternal life?