We all know who is the goddess of wealth & Prosperity , isn’t it? Goddess Laxmi and she is the dearest wife of lord Vishnu, the creator of this universe. 

 
It’s clear We all know about goddess Laxmi, but very few people know about goddess Alaxmi, who is another goddess but unpopular for known reasons.
She is another wife of Lord Vishnu. By the way lord Vishnu has 16108 wives out of which 8 are avatars of goddess Laxmi (Alaxmi is one of them) and rest 16100 are the apsaras of heaven and they became Vishnu’s wife because of a boon from Maharshi Asthavakra.
 
Now coming back to Goddess Alaxmi. 
Alaxmi otherwise known as Jyeshtha is the elder sister of Laxmi and is exactly opposite of what Laxmi is. If Laxmi is the goddess of wealth, prosperity, fortune then Alaxmi is the goddess of misfortune, poverty and bad luck. Her Vahana is donkey. She at times take the form of Owl which is said to be Laxmi mata’s vahana. It’s believed that owl is the symbol of arrogance and stupidity which always accompanies fortune (Laxmi mata). This is the reason why it is said with wealth comes arrogance and stupidity. That’s actually goddess Alaxmi accompanying her sister goddess Laxmi. It is up to us whether to accept goddess Laxmi or Alaxmi at that time. It’s always believed that goddess Alaxmi always accompanies her sister although in invisible form. Those who find her along with Laxmi and avoids her are the ones who prospers. This is mostly the reason why people worship Laxmi sitting on Padma and not on owl.


 
While lord Vishnu was creating the universe he always wanted good and bad to co exist so that we all should understand them and decide whom to accept and whom to avoid. It was said she was created during samudra Manthan which gave out both good and bad. That’s why he created both the sisters. Alaxmi is believed to have married to sage Dussaha but he soon discovered that his wife can not stand auspicious things , she is always foul mouthed, arrogant, brings quarrel and misfortune to wherever she goes. So, he complained to Vishnu and eventually left her and that’s when Alaxmi came to Vishnu and requested him to accept her and in this way she became his wife. She is considered as one of the 8 forms of the supreme power (Parashakti which again is related to Laxmi who is another form of Maa Shakti) who regulates human lives in different ways. That’s why initially I said all 8 wives of Vishnu are related and are avatars of Laxmi. They all form the supreme power or Parashakti. 
 
It’s believed that ladies mostly worship her so that they don’t have her qualities. It’s believed that she is worshipped with lemons and chillies outside of the house so that she remains outside and doesn’t come in. Upon her name is the Jyeshtha nakshatra related. If a bride enters a family in the Jyestha nakshatra, then her eldest brother-in-law is believed to die. Goddess Alaxmi’s images are rarely worshipped today. They are kept unrecognised in neglected corners in temples or thrown out of temples.
 
It’s said one day both the sisters asked Vishnu who among them is more beautiful. To which Vishnu replied “To Laxmi, when you are coming you are the most beautiful and to Alaxmi, when you leave you are the most beautiful “. it’s evident that both will be accompanying you. In Hinduism, both the auspicious and inauspicious are duely recognised and respected accordingly because if there is no strife we will never understand the value of peace, if there is no poverty wealth will never be valued, if there is no misfortune then fortune will never come. So without end there is no significance of beginning and hence without Alaxmi we will never understand the value of Laxmi. This is the law of our nature or Prakriti, the sooner we understand it the better it will be for us.

External references:
Wikipedia
Quora