Cruelty under Indian law includes both physical harm and mental suffering that makes living together impossible:

• Mental Cruelty: Constant humiliation, false accusations, restricting freedom, or prolonged silence that causes mental agony.
• Physical Cruelty: Any act causing bodily harm, injury, or danger to life, limb, or health.
• Legal Significance: Under Section 13(1)(ia) of the Hindu Marriage Act, 'Cruelty' is a valid ground for divorce.

Desertion refers to the intentional abandonment of one spouse by the other without sufficient cause:

• Willful Abandonment: Leaving the spouse without reasonable cause and without consent.
• Duration: Must be for a continuous period of at least 2 years immediately preceding the divorce petition.
• Constructive Desertion: If one spouse is forced to leave home due to the other's cruelty, the aggressive spouse is considered the deserter.

Drafting and sending a legal notice immediately serves crucial strategic purposes:

• Stops the Abuse: A legal notice shows you have legal backing, acting as a strong deterrent to further harassment.
• Creates Evidence: It puts on record specific incidents of cruelty or the exact date of desertion, which is vital for court cases.
• Option for Settlement: It gives the spouse a chance to rectify their behavior or agree to a mutual separation to avoid litigation.