I have sent correspondence about ten times to my Congressmen and Senators. I have received a good reply (although often just saying there is nothing that they can do) except for the one time I contacted Jon Kyl and unfortunately mentioned data about his campaign donations from Monsanto - I was writing about a bill he sponsored that I thought would have made it difficult for small farmers to survive economically and make community gardens difficult because of regulations. No response on that correspondence.
Those interns have a pile of form letters they send for about 99% of (e)mail they get, and if you happen to catch their attention you might get more than than the usual tick mark in a spreadsheet (for/against X). Which at best might be as much as a sentence or two in a weekly correspondence summary which may/may not be read by your representative depending on how seriously they take their job.
Everything has become so my team vs your team... you are bad because you think differently...
In places like the usa I don't think politicians should expect privacy or peace. They have so much power compared to the citizen and they so rarely further the interests of the general population in good faith.
Given how they treat you, it's best to abandon politeness (which only helps them further belittle your meaninglessness in their decision making) and put a crowd in front of their house, accost them at restaurants, and find other ways of reminding them how accessible and functionally answerable they are to the people they're supposed to serve.
Politicians just know that it's better to be nice to people who seem to like you or are engaged with the system, since they want to keep getting your vote. If not then the person isn't worth your time.