No, this is a fundamental misunderstanding of representative democracy. You vote for the candidate who represents your views on the greatest number of issues; you can never expect a candidate to agree with you, or indeed with the majority of constituents, on every issue. If this was required, every candidate would be de-selected at every election!
Don't think so. There is no candidate to vote for in a referendum just an option. Surely the MP should carry out the wishes of the majority of his constituents.