ANSWER:
You are not obliged in Islam to serve your in-laws and you are not sinful for not giving his family time or care however, you must not stop him from serving them as this is his obligation. You need to be diplomatic and tactful as his family are most likely whispering bad things about you in his ears. If you are not careful, by saying the wrong things or behaving in the wrong way, this might confirm what they are filling his head with. Don’t nag him and don’t demand his presence. Tell him that you miss him and that his daughter misses him and that you would be waiting till he is ready, without pressuring him.