All perfect praise be to Allaah, the Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.
First of all, we congratulate you for the blessing of Allaah on you by making you a Muslim and we ask Allaah to make us and you firm and steadfast on Islam until the day we meet Him.
A Muslim should always remember that this worldly life is a trial; Allaah tests His slaves with good and evil, and in this case, a believing man or a believing woman should abide by patience, which is an act of worship, and there is a good outcome in patience in this life and in the Hereafter. For more benefit on the virtues of patience, please refer to Fatwa 83577.
Secondly, there might be a difference of opinion between the Muslims on the issue of demonstrations or practising political work, or any other matters of Ijtihaad (a juristic opinion on matters which are not specified in the Quran or the Sunnah); however, the etiquettes of differing should be respected and each person should respect the opinion of the other, and avoid being fanatic and exchanging accusations or entering into declaring one’s alliance or enmity due to this.
Thirdly, a Muslim should help his Muslim brothers/sisters in goodness, so he should help the needy and facilitate the matters for a person in difficulty; these are among the most important principles of brotherhood in Islam. If the Muslims you mentioned did not help you, then seek Allaah's help and do not seek the help of anyone else, as all good is in the Hands of Allaah, and the one who has hope in Allaah will never be disappointed.
Fourthly, marriage is a good thing which you should take the initiative to do. Indeed, it is permissible for a Muslim woman to propose herself to a righteous man to marry her, as we clarified in Fatwa 82471. If you do not find someone who is at a high level of righteousness to marry, then you should accept someone who is acceptable with regard to his religion and moral conduct in general, i.e. someone who observes the religious obligations and avoids the grave major sins. Marriage may be the best solution to get out of your state of sorrow and difficulty. For more benefit, please refer to Fatwa 89505.
Hence, if you find someone whom you are pleased with and who has a good physique, then this is good, otherwise you should not reject someone who is overweight and the like as you mentioned in the question, as long as he is at least acceptable in his religion.
Fifthly, one should distinguish between Islam and its principles on the one hand and the bitter situation of some Muslims and their bad behavior on the other. Rather, a person should abide by and follow the truth even if it is abandoned by others. The renowned ascetic scholar Al-Fudhayl ibn ‘Iyaadh said: “Follow the path of guidance and do not be bothered by the small number of those who tread it, and beware of the path of misguidance and do not be fooled by the large number of people who destroy themselves on it.” So, reason and wisdom necessitate that we judge the behavior of people according to Islam, and not judge Islam according to the behavior of people. For more benefit, please refer to Fatwa 127523.
Meanwhile, you should be careful of the help provided to you by some non-Muslims lest it may lead you to be affectionately attracted to and influenced by them or being an ally to them as in this case, it would be a great calamity. Allaah Says (what means): {You will not find a people who believe in Allaah and the Last Day having affection for those who oppose Allaah and His Messenger, even if they were their fathers or their sons or their brothers or their kindred.} [Quran 58:22]
Sixthly, it is worth mentioning here that it is allowed to keep a cat or similar permissible pets, but one should be moderate about this and avoid exaggeration, like considering losing a cat as a great calamity or that the matter of burying it would be a great concern to the extent of blaming someone for not helping in this.
Finally, we ask Allaah to facilitate your matters and open your heart to the truth.
Allaah Knows best.