Feeling like the worst mom

For months now my 2 year old wants nothing time do with me unless its bed time. She used to want only me but when the start of the semester hit and she had to stay home with dad she changed to wanting only him. No matter how much we do together or play together she doesn't want me to do anything for her. I hate this because I feel like I am failing as a mom.. I feel like she doesn't love me anymore....