Relationship going downhill

I have been married to my husband for seven years in January we have struggled to have kids for six years we just had her baby girl this past April ever since she’s been born our relationship has gone downhill I have even considered divorce or time apart he says it’s my fault but I don’t take care of him the way I used to and I have tried to change my ways but I don’t see no change from him I have heard the six and seven year of marriage are the hardest and I see why I don’t know what to do