"but if my partner wills me money am I then entitled to receive it. "
Yes. But.
His wife is entitled to a share of his estate and could contest any will which does not provide for her. I appreciate that this is a very difficult time but your partner probably should be talking to a solicitor. One possibility is to put monies into a joint account with the express intention of benefitting you. Monies in a joint account are not included in an estate.
Also, there may be tax liabilities for you depending on the amount.
mf