I just need legal advice..I cannot go in a battle without any weapon...

I just need to know what i need to do... I am married with 1 kid, but we have been separated for almost two years. My husband has been living with other woman. Take note the woman is married also she is the wife of my husband's close friend. They are living together and they have 1 kid..the situation has been very complicated. after the incident happened i just kept quiet i did not make any action. What they did is that they act as really husband and wife. we are living on the same town.people see them anywhere together. I just let things happen but now i think i need to do something about it not for my own sake but for my kid. because the support that my husband has been giving is not enough he will just give financial support if he has but if he doesnt hav sorry for my kid. I think i need to fight for my right and definitely i need to do something because my kid has been neglected already.
As of now they are living in an apartment but my husband started building their own house it is being built in the land they acquire from their parents. when he got that land we are already married so it is conjugal right? what is the best thing i need to do? what case il be able to file? Concubinage? im hoping a reply on this before i make an action.

if i were your husband's lawyer, i would argue that you consented to their relationship because it has been so long that you knew about this and your did nothing.

so first, gather your evidence that they are living together as husband and wife. start establishing that you do not consent to their relationship. you or your lawyer can send a letter to him demanding that he end the relationship and provide support. add a claim to the house he is building.

find a way to get the birth certificate of their child and see who they listed as parents.

it depends how he acquired the lot. if he inherited it during the marriage, it becomes his exclusive property. but the house itself should be considered conjugal.

Thanks for the response very much appreciated. The surname of the child is my husband's surname and the middle initial is the maiden name of the girl...even if i did not make any action before do you think i can still make action now?? will it be possible? Their kid just celebrated 1st bday in a restaurant can be the pictures there that they are together be the evidence..I just want to make action now because i found out that my husband will not be supporting my kid anymore so the right of my child is being deprived. Can i still make an action even if it happened a almost 2 yrs ago...What possible case can i file? o r what do i need to do?

if you have enough docu evidence, send a letter stating that you are not consenting to their relationship, and if it will not end, you will file a case. add your demand for support for your child.

i think they will try to nego with you and you can make your demands.