Honestly I really don't know. On a personal level whenever I've had people close to me start to go anti-immigrant rants I try and explain some of the systemic issues that contribute to immigration. But most of the time it just feels like it goes in one ear and out the other. It doesn't help that Western media constantly bombards people with anti-immigrant storylines.
And as others have stated there really isn't much of a Western "left" anyway, especially in the electoral realm. In the US the Democrats, who are mistakenly labels as the "left", contribute just as much to the anti-immigrant fervor as the right. I hate to sound doomer-ish, but I don't really see any group that is nominally left leaning and has enough reach in the US mounting a true alternative to the anti-immigrant sentiment that has been festering and growing. Maybe I'm just surrounded by too many people that have developed anti-immigrant sentiments and its clouding my judgement of the situation.
Honestly, if its people that know your situation and you've pointed it out multiple time and they still go meet you unmasked, then no. Its not weird to be disappointed.