Wedding invitation

I am invited to an ex-colleague's wedding dinner. I dont know this person exceptionally well, but I guess he is inviting me out of politeness.

But I think I am not going, and I will be informing by thurs I think. I am going to give a vague reason like it's a birthday celebration of a friend (a reason that never fails to work) and just give an ang bao of $50.

I dont want to go mainly because I dont wish to make small talk with people, abeit they are ex colleagues - people whom I know. But this is also precisely why I shouldnt go, cos I dont wish to give anyone chance to corner me around a round table of auspicious sounding food and question me.

And so!... I'm embracing solitude anyway.