In the past 2 weeks I've sent the same friend a happy birthday text, a text to say congrats on passing an exam, and a good luck with your house move text. Not once have i received a thank you back (we have exchanged messages about other things so I know she has a working phone and hasn't stopped speaking to me). I don't expect her to have acknowledged all 3 but is it too much to expect someone to send a quick thx back for at least 1 of the 3?