"If the Government's stance that immigration is making the country richer, how come the country is still in a trade deficit while at the same time we have record levels of immigration?"
But we run a surplus on both the services account and the capital account. We are mainly in trade deficit because we import lots and lots of cheap clothing, electrical goods etc that we could not produce at the same cost because other countries have a comparative advantage over us. You are conflating this with population growth.
At the same time since 1998 living standards have risen in the country since 1998. The country has not "got poorer", it may feel that way since the crash but its not true.
"Internal consumption does not make the country richer, it shuffles the existing money around"
Incorrect, it increases the likelyhood of investment and increases the amount that the government can spend investing in schools, education etc. It also increases the amount of FDI, all, of which increases the wealth of the country and its productive capacity.
"We are so badly off, that even with spending cuts, we're still borrowing more money."
Austerity was a political choice not a necessary one, the in initial round choked off growth in 2010 and has prolonged the need for it. In times of true austerity taxes are not cut for the wealthy.
"If the increase in population was generating a commensurate amount of exports, the said companies and their employees would be earning enough from imported money to pay for their own houses and be paying a lot more taxes to give to the Government to give them the means to build more schools and indeed enough to pay the doctors. "
Conflation again, we are not building enough homes because the priovate sector banks land and waits until it will be extremely profitable to build.
The schools and doctors argument? Well again, Oxford University say that immigration has had a positive effect on the NHS, UCL say that a reduction in immigration/making immigrants go home would be detrimental because the fall in demand wouldn't be great enough to make up for the cuts in funding that would come with lower tax take. The OMOU say that most EU immigrants are young adults who do not really impact on the provision of services.