Hon, I think it's great that you're putting in this hard work to save your marriage. But be careful of doing "big" things to surprise her. Eventually you're going to run out of big things and then what will you do?
Rather than doing all these epic gestures of love, look at improving the 'every day' with her. Be present in both body and spirit. Take the time to listen to her. Pretend to be interested in her interests which you really don't care about. Give her hugs without expectation of sex (unless sex is something she's missing). It's about nurturing your marriage in frequent, small ways
Never regret anything that has happened in your life. It cannot be changed, forgotten or undone. So, take it as a lesson learned and move on.