"Why should someone have to pay alimony?" - If a couple divorces and one of them doesn't have the skills to get a decent job, then it makes sense they be supported for a limited period of time, to allow them to gain the skills to get a job or to find a job with their current skills. A man or woman who was a stay-at-home spouse, was being supported by their partner when married. Divorce shouldn't leave them on the street to fend for themselves or to be a burden to the taxpayers. FYI, it's called "spousal support" these days, instead of alimony, and is not often awarded because in the majority of couples today (at least in the US) both parties work, because that's what it takes to have the lifestyle they want or because that's what it takes to cover their basic expenses.
"Basically, someone wants a divorce and usually the woman asks to get alimony. Why should a grown *** woman (or man) be entitled to money for living expenses?" - See my answer to the question above.
" And usually they get this on top of child support too! " - Child support is to help support any CHILD/ren the couple had together. It covers a portion of all the expenses to raise a child, but is far from being enough to support both the custodial parent and the child. Spousal support is to help support the ex-spouse (whether the couple had kids together or not).
"You want to be all independent and have a divorce, yet you still want money from the other person?" - You assume the person requesting support is the one who initiated the divorce. That is not always the case, and even if it is, as mentioned above, if the person making the request is unable to financially support themselves, then it makes sense to request their former spouse do so for a period of time that will allow them to get on their feet, financially.
"All while the person having to pay is killing themselves working and having to pay everything on top of their own stuff." - Maybe they are, and maybe they aren't being financially stressed by having to do that. Either way, they chose to legally bind their life to someone else, so they can't just leave that other person high-and-dry if the marriage ends. You claim to be a 'girl' so do you think it would be okay for your husband to support you while you two were married, so you could be a stay at home wife/mother and tend the home and raise the child, and then one day he decides to divorce you (or you him, for whatever reason). You'd be okay being left with no marketable job skills to get a job above minimum wage, while trying to support yourself and your kid? If so, then you're foolish and unrealistic. As I mentioned previously though, spousal support is rarely awarded anymore, because most of the time both parties work full time jobs, because that's what it takes to have a decent lifestyle in many parts of the country...so your argument is nearly a moot point. It affects few people (having to pay spousal support) and for those it does affect, most of them only have to pay for a limited amount of time (the other party is expected to take steps to be able to financially support themselves as soon as possible).