100% yes, you can do this on your own. There is no guarantee that you will save your M, but it's the best chance you've got.
7 weeks ago, my H was 100% certain he was going to D me, and couldn't get out of here fast enough. After 5 weeks of DBing (with lots of little baby steps in between), he told me he really appreciated all the positive changes I have made, that it reminded me of why he married me, and that he is open to the possibility of fixing things between us. He still moved out and we are separated, so I have a long way yet to go, but I am thrilled with the results so far - not only because I feel hope for my M, but because I feel hope for myself.
Read the book, get going on your 180s and GALing, and post here often - you will get tons of excellent advice, information, and maybe some gentle bonks on the head when you need them.
me: 44 XH: 42 M 11 years D10 and S8 Bomb drop 9/27/13 D final 7/1/14