Marriages are made in heaven. It has been predestined whom you will marry. So you had got married and you have lived with him till God had marriage in store for you. If your friend is going to get married to someone else, you can call it fate and you should get reconciled with such things which are beyond your control. Perhaps one day someone will propose to you and you could choose him if you like. There is little point in checking the horoscope compatibility between two people who are not planning to get married. And astrology can never say with whom you will get married by looking at the horoscopes.
Depression is a state of mind and it will get over by time. Suicide is a futile action since you cannot die if your time is not up. Sydney Sheldon tried to commit suicide five times and he failed miserably and later died due to old age. So do not even think of your threat of suicide.