HiCustomer Thank you for asking your question on Just Answer. By the way, it would help me to know:
-What are your ages?
-Are you married?
-How is he controlling and nosey?
-How long have you been together?-Could you explain your situation a little more?Thank you again for trusting me with your problem. Please reply as soon as possible so that I can finish answering your question.
If you work and contribute to the household income you have the right to say who looks at your finances and who doesn't. It sounds like your partner doesn't care that his parent do this or doesn't want to upset them but he should also not want to upset you seeing that you are or have had his child. This is something you two have to work out before the marriage or it will only get worse once you are part of the family. Tell your husband that you feel disrespected by his parent and him when he sit back and allows this to happen without any thought about your feelings and that you are a mature adult and doesn't need to be babysat when it comes to spending money. Tell him before you are to be married this has to be worked out because you will not deal with this the rest of your married life.
There has to be some boundaries as far as what the parents can and can not do in your household especially when you get married because once you are married you should forsake all others. Don't just let this go and allow his parents that much power, take your power back before you take his name. Maybe you should talk to the parent in a nice way but tell them that this really bothers you and you respect them and only ask for respect in return. Don't go into this marriage without some understand about how you feel if your husband isn't going to respect your feelings then make his parents respect your wishes as to how you feel about then nosing around in your finances and family life. He is 30 years old so he should have been able to separate his life from his parents lives by now.
Maybe tell him either he deals with it or you will deal with it on your own and see what he says do it in a way that it doesn't end up in an argument and puts a riff between the two of you but you have to let your feelings be heard and understood. I hope was able to help in some way and if you still need help I am here for you.