It is certainly worth keeping.

You can prune forsythia very hard and it will recover but you may not get very many flowers next year.

An alternative would be to prune one third of the stems hard this year. a different third next year and the final third the following year.

That way you will get two thirds of the stems flowering well each year and at the end of the proicess will have a much smaller better pruned shrub without the 2-3 foot unleaved stems.

Once you have it pruned the way you want it prune imediately after flowering each year

Thanks Anchorman i hate throwing shrubs/plants away! when can i do this? thanks very much for your help

Forsythias are flowering now so I'd say give a hard prune in a couple of weeks unless we have sub zero temperatures. ( Forsythia would probably survive being cut in freezing weather but better safe than sorry )

Thanks again Anchorman so when i prune it ,it will be just a bare stem? is that ok? will have to put it somewhere "out of sight" for now then ha ha

When it has finished flowering I would cut it back any way you like to the size and shape you choose because it will be almost impossible to kill it. It will almost certainly come again.

Inverglen many thanks

As Inverglen said Forsythias are virtually bomb proof and you can cut it back as hard as you like( to bare stems if you wish) and it will almost certainly put out new shoots in 2-3 weeks.

There are however no total guarantees when it comes to plants!

:^)