I very nearly forgot my offering to Mara tonight. That's the problem with daily offerings rather than offering only when you need something, I guess - you have to remember it even when nothing necessarily is there to remind you of it. We've got company visiting from out of town, and I wasn't feeling well and napped for a good chunk of the evening, so my schedule is completely off. That's a reason, though, not an excuse.
In this case, I did finally remember, and I just finished lighting the candles and whispering the prayers (because it's late enough that both Amber and our guest are asleep). Eventually, a day will probably come when I miss it for some reason.
The thing is, I'm not really doing this for Mara. I mean, the adoration and the offerings are for her and her sister and Ganesha, of course. But I'm doing it because I benefit from the relationship as well. Her blessings are many and valuable, and our relationship has never been one-sided. By forgetting, I'm doing myself at least as much of a disservice as I'm doing her.
All I can really do is my best to stay focused. When I work with Mara, I am reminded of what I should be focusing on. I am reminded of my goals, and keeping her in mind helps me to focus on those things.