I've never claimed that Christianity is just 'true for me'.
I'm not aware that anybody had claimed that you'd made such a claim.
That seems to be the preserve of non-believers.
Based on what?
You don't seem to be very clear on precisely what position you're taking.
Is it, or is it not, your belief that Christianity is true and remains true whether someone believes that it is true or not, i.e. that Christianity is true regardless of what Jews, Muslim, Sikhs, Hindus, Buddhists, Jains, Zoroastrians, pagans, atheists say to the contrary?