Can You Be Too Accommodating?

This week it has become far too apparent that I am too accommodating.  In my job, dating, and social settings I am willing to do just about anything people ask me to.  It isn't like I am a door mat, If I can't do it I will say no, but if someone tells me it is important or I can do it I will usually just get to it.  
You need me to sub a class today and do my regular job because you forgot to hire a sub? Sure, I love teaching.
You want to meet for coffee at some undetermined time and place (by the way, way to make a girl feel special).  Sure, here is my number, call me and work out a plan.  
You decided not to talk to me for a month and then try a date?  OK I guess everyone needs an extra chance.  
Want me to sit with a group of students because their bus driver was lost?  Sure, I love it when teenagers sass mouth me in 100 degree heat. 
Want to go to breakfast with the family at 10? No 11? No lunch at 1?  Sure, I love food. 
Want to sing in a worship band for camp?  Sure that sounds fun.  

The above question and answer thing may seem totally silly and extreme, but it is almost word for word what has happened over the last week.  I have always been accommodating for people and I never thought that much about it.  It never was much of a problem for me.  If I can help you I will.  If my schedule is flexible I can make the adjustment.  If this is something that is really important for you I will do what I can for you. 
Well it all ends today!  That's right folks, I am done bending over backwards and making my schedule work for you.  It is time YOU make your schedule work for ME!  
Woah that last one was a little bit over the top.  I am still going to do what I can for people but perhaps take a chill pill when I just cannot do something.  
Perhaps you are asking me what has triggered this new attitude.  I was reading through the last 5 days of this social experiment 40 Days of Dating.  

40 Days of Dating

For 40 days two friends Jessie and Tim decided to date for 40 days and record their relationship.  For the first 30 days or so I was sure they were doomed.  They would fight and break up and not agree about most things.  Then around day 30 I was sure they were in love.  Things seemed to work and I had hope for these two crazy kids.  

BBC News

Well enter days 37- 40.  I should say SPOILER ALERT!  They go to Disney world for a vacation together and then break up for sure.  Well they just decided they were not going to keep dating on day 41.  I was super disappointed for these two strangers.  I was really hoping they would get over themselves and in the words of Tim Gunn, "Make it work!"
The thing that stood out to me the most was when Tim remarked that the reason he did not want to stay with Jessie after the experiment was that she was "too accommodating."  She cared to much about him, his health, and his happiness.  This struck me as odd and maybe true. 
Right now my struggle is in how do you accommodate others without being accused of being too accommodating?  What would you say is the balance that we all need in this area?  Help me stop helping others!