Amina Inloes

There is no Islamic problem in wearing niqab in some places but not others. However, sometimes there is a cultural idea or social pressure that someone who wears certain types of garments should not be seen differently. So you should decide what you feel is best for yourself. Sometimes an advantage of trying new clothing in some places is it gives us a chance to experiment with  it and see whether or not it is something we want later in life. 

Yes

Marriage is recommended in the sunnah, and in a good situation, can provide stability, security, support, spiritual blessings, and happiness, and women in particular (even today) tend to enjoy a higher standard of living and more security when married. Of course, sometimes it doesn't work out well.  Anyway it is optional, and some important sacred figures like Hazrat Maryam (a) were not married (in the view of Muslims). 
 

This is a Shii view, and some Sunnis debate whether marriage is obligatory or not (although a good number of Sunnis would say it is not). 

Yes

It's not unusual for people who are drawn to healing others to also have a strong spiritual side. 

If you're already on track to being a doctor and can realistically complete your medical education, it's worthwhile to finish it. This will enable you to serve people wherever you live, and also help you to have a decent income. (Sometimes, people who study Islam struggle financially.) A lot of people who study Islam have degrees in other subjects (such as engineering or medicine), and what you study now can help guide you in the future.

Although I haven't been to medical school, a lot of people seem to have meltdowns partway through, and so it's also worth considering whether you genuinely are called to a different life path, or you are just feeling overwhelmed with the stress and challenges and just need to hold on.

You can still dedicate time to worship as much as you are able (it is often about quality rather than quantity of time!) and, in the future, also on studying more about Islam.

If you are living with him and want to move away, but are financially dependent, afraid to leave, etc., the best thing is to find someone reliable who understands your circumstances who can advise you on the practical options available. 

It would also be helpful to find someone whom you can discuss the psychological aspects of your situation with, since it can be difficult to leave an abusive situation, even for someone who is financially and socially independent. 

For instance, you could speak to a trusted adult with life experience, a counselor/psychologist, or a charity worker.

If you are in physical danger or being trafficked into illegal/dangerous jobs, this is especially urgent. 

Later, you can consider how you may wish to keep ties with your father. "Keeping ties" can mean many things and in abusive situations may mean keeping more distant ties.

There isn't a religious requirement to live in the same home or be in close contact, but sometimes it can be difficult to leave a situation for financial, cultural, psychological, or other reasons. 

Personally, I would find it weird to have it around. However, according to Ayatollah Sistani and Sayyid Khamene'i, it is not necessary to get rid of statues of humans. 

Here are some historical Abu Bakrs:

https://en.wikipedia.org/wiki/Abu_Bakr_(name)

It is normal for some people to see lights, colors, and so forth when their mind is in a relaxed and contemplative state.

I wanted to add that it is very nice of you to take the trouble to look into what he should or should not be eating, and he is fortunate to have a supportive parent. I do sympathize with the dietary restrictions and allergies.

If it is available and affordable, and if you have storage space and can take delivery at home, halal meat can sometimes be purchased online. You may have already looked into that, but just putting it out there!

It is deeply unlikely that Ibn Saba was a real person. There are strong arguments against his existence, and the reports on him are weak and via a questionable reporter. 

It seems that these reports may have spread, despite their weakness, because they present a nice and cozy picture of early Islam, in which everyone is getting along and there is a convenient explanation for disagreement in the community by attributing it to a plot. This is desirable to those who want to see all the sahabah as perfect. However, in reality, there was a lot of fighting and disagreement during the first three caliphates, and afterwards, and the real picture is not nearly as comfortable.

The Shi'ite Encyclopedia (which is available on al-islam.org) has a very comprehensive discussion of the sources of these reports and their reliability and other factors.

Among Shi'i sources, Rijal al-Kashshi lists him as a person but rejects him. Anyway, this seems to be responding to the narrative that was popularized. As for the single mention of his name in al-Khisal in a dialogue, there is insufficient context to say anything meaningful about it, except that, were he taken as a real narrator, he would have been rejected, but most Shi'i scholars hold that he didn't exist. 

There isn't a fixed difference between Sunnis and Shi'is for determining the beginning of the month of Ramadan. However, many Sunnis follow the announcement from Saudi Arabia for the beginning of the month of Ramadan. Unfortunately, sometimes, Saudia Arabia announces the sighting of the moon at a time when it is astronomically impossible to see it. (One can verify this using astronomical software) 

Most Shi'is follow local moonsighting (or via a shared horizon; either via the naked eye, as per Ayatollah Sistani, or with the help of an optical aid, such as Ayatollah Khamene'i). Some Sunnis do this also. 

Where one is in the world also affects differences in determining the beginning of the month. (You can visit moonsighting.com to see graphs of where the moon is visible and when.)

Anyway it is fine to fast on the last day or days of the month of Sha'ban, but counting the days of the month of Ramadan is useful for observing laylat al-qadr.

It is good to pray for forgiveness regularly, as long as it does not become too much of a habit and lose sincerity or focus - tawbah should be from the heart.