The weapons already exist, they cost "nothing" to give them to another country. Do you want to pay nurses and doctors in javelins and himars? You could argue that it costs money because this means that they will have to be replaced by new weapons but thats a different discussion.

And the same lawmakers grandstanding on the war in Ukraine have spent the last eight years helping Saudi Arabia brutalize Yemen.

It's almost as if helping a country defend itself against an invader is more morally acceptable. And it's also happens to serve the US interests(hence the bipartisan support). The story is kinda simple, a bigger country wants to conquer a smaller country because the smaller country is doing things the bigger country doesnt like.

Do you think countries and democratically elected governments have the right to choose their foreign policy? Would you be ok if the US invaded Mexico if Mexico decided to join an alliance with China? Because this is what is happening in Ukraine.

In Yemen, the US has no interests and it is basically a civil and proxy war between Saudi Arabia, Iran and Al Qaeda. It's kinda hard to find even relatively "good guys" in this conflict(other than the normal people suffering).