That's politics in the modern era though. Atlee was possibly the last politician here to change things for the better overall. You could argue that Thatcher also did but that she also made life worse for many as well.
Politicians say one thing one week, then do a complete U-turn the next, as we've seen. But most aren't completely unpredictable, with little or no regard for the truth. It is what it is. One day we might get back to politicians having integrity and being honest, instead of having only self-interest and/or simply toeing the party line, however illogical that may be.
Why get yourself worked up about it? We have to try to do the best we can for ourselves, our families and our communities.