There are many ways of expressing true love in written form, and poetry is perhaps one of the best ways, although writing songs is another good way of expressing how you feel, although the two are quite similar, as song lyrics are written in a similar way to poetry.
There are also books and short stories which contain the theme of true love, although these tend to look more into the feelings of other characters rather than your own feelings, but it is good to have characters that you can relate to.
Letters can also be a good way of expressing true love but a poem is probably the best way of expressing true love to someone as you can play around the language more and include metaphorical language to express how you feel. Poetry is also more famously associated with love.
There are also books and short stories which contain the theme of true love, although these tend to look more into the feelings of other characters rather than your own feelings, but it is good to have characters that you can relate to.
Letters can also be a good way of expressing true love but a poem is probably the best way of expressing true love to someone as you can play around the language more and include metaphorical language to express how you feel. Poetry is also more famously associated with love.