1 month into my marriage I found out that my wife’s divorce was not biblical. She had told me that her husband cheated on her for years and she finally was able to leave him. I just found out that she had a number of different affairs during her marriage and while separated. I believe this is definitely false pretenses considering she had no remorse or conviction during that time for what she did. In fact all of these was found out by me looking into matters and pressing/probing. Had any of this been disclosed to me before hand I would not have married her because I would then be committing adultry as well. I also found out that she had sex with someone while we were in the beginning stages of our dating relationship. Am I able to get an annulment? And/or does this qualify as a biblical divorce? All trust has been broken due to her horrible deception. Please help. Thank you.
There are certainly two issues at play here, a legal issue and a Biblical issue.
From a purely legal perspective there are often differences between an annulment and a divorce. I'm not a lawyer and my knowledge of this kind of thing is both limited and theoretical (and of course for good measure laws vary from place to place). My understanding is that, in general, an annulment effectively unwinds the marriage as if it never happened, whereas a divorce acknowledges that the marriage existed but is now finished. If you can get an annulment that may be cleaner although I believe some areas only allow an annulment if the marriage has never been consummated. There are probably other requirements that would need to be met over and above "I changed my mind". You'd need to talk to a lawyer in your area to figure your legal options.
As far as the Biblical perspective is concerned you'll have a lot of things to consider, not least how you interpret that passage in Scripture. I assume you're looking at Matt 5:31-32, which reads:
Matthew 5:31–32 (NKJV): Furthermore it has been said, ‘Whoever divorces his wife, let him give her a certificate of divorce.’ But I say to you that whoever divorces his wife for any reason except sexual immorality causes her to commit adultery; and whoever marries a woman who is divorced commits adultery.
The whole issue of how to interpret this can potentially raise questions. Jesus talks of divorcing a wife and makes no mention of divorcing a husband. Perhaps that was cultural - in the time Jesus walked this earth I don't imagine it was even an option for a woman to divorce her husband. We might make an assumption that gender roles can be flipped in this day and age and use it to justify a wife divorcing her husband for sexual immorality - although it doesn't seem inherently unreasonable given our culture doesn't regard a wife as pretty much the property of her husband we need to be aware that making such an assumption reinterprets the words of Jesus in a manner that may not be appropriate.
The part where Jesus said "whoever marries a woman who is divorced commits adultery" is of potentially greater concern. Read literally it offers very little scope for a woman who is divorced for any reason to remarry without her new husband committing adultery. Taken in isolation it would mean that even if we allow gender roles to be reversed in the preceding comment, an innocent wife who left her husband because of his unfaithfulness is still left in a situation where she cannot remarry without her new husband committing adultery.
If an assumption is made that gender roles can be reversed throughout the whole of this theme it is at least a little more forgiving. If the only reason a husband can divorce his wife is for unfaithfulness (presumably hers, rather than his) and the prohibition on remarrying then applies to the unfaithful wife, it isn't an entirely unreasonable argument to make that, flipping the gender roles, a wife may divorce her husband for unfaithfulness (in this situation presumably his rather than hers) and to maintain consistency it would make sense for the unfaithful husband to be prohibited from remarrying without making his new wife guilty of adultery.
Of course another big difference between the culture when Jesus walked the earth and culture today is that of mobility. If Jacob the carpenter divorced his wife due to her unfaithfulness the chances are everybody would know about it, everybody would know her, and everybody would know that she was an adulteress and divorced because of it. Chances are few people would even want her as their wife knowing her shame and anybody who was willing to overlook her shame (for whatever reason) could reasonably be expected to know who it was they were marrying. With the anonymity offered by big cities these days, and the increased mobility that allows people to simply go somewhere else far more easily than your 1st century stonemason could even begin to imagine, it's far easier to imagine situations where people lie about their past with no realistic way for people to find out for sure.
There's also a big difference in situations based on your knowledge of just what was happening. If you're looking at Scripture that is very clear "God says no" and you decide that God doesn't really mind any more that's a very different situation then if "God says no" but your understanding of the situation is that it is different. To take a silly example, if Scripture says "thou shalt not put beans in thy nose" and you decide it's no longer relevant and put beans in your nose, or if you decide to be legalistic and argue that it doesn't clearly state you mustn't put peas in your nose, then one way or another you are making a decision that the rule doesn't apply to you. If Scripture says "thou shalt not lie on a bed with green sheets" and you visit a hotel that has a very comfortable bed clearly made with white sheets (having clearly requested a bed with no green sheets), and only later you come to realise that under five white sheets there's a green sheet, then your only failure (if it can even be called a failure) is in trusting a situation as you saw it. In legal terms there's a difference between not knowing the law and not knowing the situation.
Scripturally speaking this is a situation where you will probably need to decide exactly how you believe you should apply the words of Jesus to your life. This will include just how literally you want to apply the words of Jesus, and how forgiving of yourself you are willing to be given you were deceived.
This really doesn't look like a good place to be, so I'd strongly suggest talking to a local minister you trust as well as a local lawyer.