Hyphenating Last Name???

I'm expecting a baby girl July 23... My husband and I decided on a name for our baby girl (Elaina Marie) and announced it before he told me he was leaving the marriage.. I've been thinking lately about hyphenating our daughter's last name and giving her my maiden name and his last name... I haven't talked to him about it and I really am not doing that to be vindictive or anything but if I did do that, it would give my daughter the same initials as my beloved grandmother... Opinions anyone?