How did Darcy feel about separating Jane and Bingley?

Darcy's letter says that he admits that the impropriety of the Bennet family made him hope that the two would not marry, but that his main reason for preventing Bingley from proposing to Jane was that he did not think that Jane had any particular regard for Bingley. The only part of his conduct which he is uneasy about is that he concealed from Bingley his knowledge that Jane has been in London for the past few months.