Jagg provides some good guidance on mechanics of improvement. Let me see if I can address a little of what to do now.
1- You didn't fail, you found ways that didn't work. Find the Thomas Edison quote "I didn't fail 1000 times, I found a 1000 ways it didn't work" in a nice format online. Print it and post it in the team area.
2- Don't kick yourself. This isn't easy to do. Right now you're in what we call the "Shu" phase. You know what the Scrum rules are and you're trying to hold to them. This is good, keep trying. Just don't kick yourself if you fail. See #3.
3- Start asking "What can we do to get better?" Instead of "we failed" move forward to "now what". Go back to Jagg's post for adivce here.
4- Shorten the Sprint. It seems highly counter intuitive, it works. Shorter sprints means there is less to do. Think of it this way, you have 30 stories in your month long backlog, that's 30 opportunities for your grooming or planning to go down the rabbit hole. If you're sprints are two weeks, you only have 15 stories. Your odds of a rabbit hole just dropped in half.
5- Good agenda planning. One of the big curses of any meeting is the lack of good agenda planning. A Daily Standup even has an agenda. That agenda is "Team Member 1, three questions. Team Member 2, three questions."
For Daily Standup, you can even go as far as divde 15 minutes by the number of team members and set a timer. Timer goes off, you move on. Remember, Standup is quick, any discussions go to the "follow up" pile.
For longer meetings, the secret sauce for agendas is to do your agenda by clock time, not minutes.
Do:
1:00 - Start
1:03 - Agenda review
1:05 - Agenda Item one
1:30 - Agenda Item two
1:50 - Action Item review
2:00 - Close
Don't:
5 minutes - Agenda
25 minutes - Agenda Item one
etc.
Again, set a timer if you need to. If you have 4 hours labeled as "Sprint Planning" you won't ever get everything done. Figure out what needs to be done and how much time it needs. Create the agenda, send out the agenda before the meeting, post the agenda on a white board or easel paper where everyone can see it.
Cheers...