You should ask your wife what is the reason behind this, have you committed any fault or may be what is disappointing her the relationship? She would tell something and then try to improve that as soon as you can that will  defiently give you the results. You can also try to make her understand that this is creating mental pressure on you and ask her to  stop.
 If she does not then you can tell your in laws about her misbehave; they  can talk to her and if she continues than you can file the complain.