Thanks a lot for your reply, it has helped quite a bit. However, I would like to clarify things further..
I am relieved that some of this behavior, that is, becoming closer with his dad, is a natural phase, but regarding my son being rude to me only when my husband is around, is that part of that, or is that due to the other issues i.e. grandparents/husband' behavior etc?
Regarding the grandparents, yes this is a 'culture' thing, (we are Indian) but after a lot of fights/struggles, this has improved a lot, that is, less of their interference etc. The only point here is, since in our absence they look after him, take him to whatever classes I put him in, drop/pick him from school etc, they feel entitled to some authority. But anyway, issues on this front are now reduced to the extent possible.
Regarding my husband, yes I agree, I will have to work on discussing these things with him, with regard to supporting me etc. His point of view is if my son is rude to me, I should handle on my own, and vice-versa when he will handle on his own without my support, which I feel is not right. He refuses to come to a counselor, but he has agreed to come to a child counselor for our son. We just had 1 session with the child counselor which was only related to providing background info etc. Am wondering if through this, I can get my husband to correct things?
One query I have is, is it possible to bring up the child normally, attempting to have a united front on parenting etc, without us being a normal couple, or having a normal marriage? My husband seems to think so, while I think it is not possible to resolve parenting issues without resolving marriage issues/having a normal marriage. And I feel, it would also help for my son to see us affectionate/nice to each other, which is not happening since the last 3-4 years.