Start collecting evidence through audio recording on mobile or recording device.
Start collecting videographic evidence by making video of her statements on spy camera, such cameras are available on online shopping like flipkart.com.
Report this to the nearest women poilce station and get a NCR, non cognizable report on this and they will in turn give a NCR number. Keep that NCR number with you, as in your absence if wife ends up commiting suicide these photos, videos, and NCR number only will help you come out clean.
As she is asking for divorce, its a golden opportunity for you. Just agree for divorce and let her go. Overall, in your case, it is very difficult to get divorce if you will apply for it, today you might be thinking, marriage, child etc what about child life etc, but when u get fed up and you yourself wants divorce, you cannot get it that easily, it will take 10s of years, by the end of it your life will be almost over roaming to court halls facing false cases etc. So if she is asking divorce, give it, marry soomene who is compatible with you.
You can always take custody of child citing mother has suicidal tendency hence child should be with you, and court will also agree, you can leave the kid with your parents to look after or arrange for baby care by aayah.
I have seen thousands of cases like yours. Women like these end up being a trouble to each and everyone in your life. As I see it, if she wants to create trouble you will also end up losing your govt job and go behiind bars, not just you but also your parents and relatives.
Be very careful.
Words of the wisdom: Stay away from bad people, in this case your wife.
Laxmi Kant Joshi (Advocate ) 17 May 2014
T. Kalaiselvan, Advocate (Advocate) 17 May 2014
If the suicide threats continue and she is still behaving in the same way without any reason, you may as a precaution, lodge a complaint about her nature and behavior and the suicide threats over silly or no issue, get an acknowledgment from the police in the form of a CSR (or NCR), preserve it safely so that suppose it happens in the future, you may be safe to some extent on that aspect. Thinking of divorce, considering the infant child is too early, tolerate with her behavior till how much ever possible and once reached a level beyond tolerance, then think wisely about the legal course of action.
Gautam Kapoor (IT professional Studying Law) 17 May 2014
Advise provided by Mr.Helping Hand and Mr. KS are apt to deal with your current situation ....more so considering your 8 month infant.